Unraveling the Mystery: A Deep Dive into the PresenceWriter DCOM Error and How to Resolve It

Windows Event Logs are often the first port of call for system administrators and power users troubleshooting perplexing system behavior. Among the cryptic entries that can appear, Distributed Component Object Model (DCOM) errors, particularly Event ID 10016, are notoriously common and often frustrating. One specific variant that frequently surfaces, especially in environments utilizing Microsoft communication platforms like Lync, Skype for Business, or even Teams integrated with other services, involves the PresenceWriter.

The typical error message looks something like this:

The application-specific permission settings do not grant Local Activation permission for the COM Server application with CLSID {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} and APPID {yyyyyyyy-yyyy-yyyy-yyyy-yyyyyyyyyyyy} to the user NT AUTHORITY\NETWORK SERVICE SID (S-1-5-20) from address LocalHost (Using LRPC) running in the application container Unavailable SID (Unavailable). This security permission can be modified using the Component Services administrative tool.

Seeing this error, especially if it occurs frequently, can be alarming. Does it indicate a critical system failure? Is security compromised? What exactly is PresenceWriter, and why is it causing DCOM permission issues?

This comprehensive article aims to demystify the PresenceWriter DCOM error. We will delve into the underlying technologies – DCOM, Presence, and the Volume Shadow Copy Service (VSS) – to understand what PresenceWriter is and why it triggers these errors. Most importantly, we will provide detailed, step-by-step instructions on how to diagnose and effectively resolve this specific DCOM configuration problem.

Chapter 1: Understanding the Core Technologies

To grasp the nature of the PresenceWriter DCOM error, we first need a solid understanding of the key components involved: DCOM, the concept of “Presence,” and the VSS framework.

1.1 Deep Dive: Distributed Component Object Model (DCOM)

DCOM is a fundamental, albeit complex, technology woven into the fabric of Microsoft Windows. It’s an extension of the Component Object Model (COM).

COM (Component Object Model): At its core, COM is a binary-interface standard for software components introduced by Microsoft. It allows developers to create reusable software components (objects) that can be plugged together. Crucially, COM allows inter-process communication (IPC) – enabling components in different running programs on the same machine to interact with each other. Think of it as a standardized way for different software pieces to talk, regardless of the language they were written in, as long as they adhere to the COM standard. Each COM component has a unique identifier called a Class ID (CLSID).
DCOM (Distributed COM): DCOM takes COM a step further by enabling these software components to communicate across a network. It extends the COM infrastructure to support communication between objects on different computers. DCOM handles the complex underlying network protocols (like RPC – Remote Procedure Call), object location, message marshaling (packaging data for network transmission), and security. When a program on Computer A needs to use a component on Computer B, DCOM makes it seem (to the programmer) almost as if the component is running locally. Each DCOM application is typically identified by an Application ID (APPID).

How DCOM Works (Simplified):

Client Request: A client application wants to use a COM component.
Location: The system (using the COM/DCOM runtime) locates the component. This might be in the same process, a different process on the same machine (using Local RPC – LRPC), or on a remote machine (using network RPC). The Registry plays a vital role here, storing information about CLSIDs and APPIDs, including where the component’s code resides and how it should be launched.
Activation: If the component isn’t already running, DCOM attempts to launch (activate) it. This is where Launch Permissions come into play. DCOM needs to know which user account has the right to start the server process hosting the component.
Connection & Communication: Once the component is running, the client establishes a connection. Access Permissions control whether the client’s user account is allowed to interact with (call methods on) the running component.
Proxy/Stub: DCOM uses proxy objects on the client side and stub objects on the server side to handle the communication complexities, making network interaction transparent to the applications.

Why DCOM is Relevant to Errors:

DCOM’s power lies in its ability to manage distributed objects, but this also makes it a common source of errors, primarily related to permissions and identity:

Launch Permissions: Determines which users or groups can start the DCOM server process. If the user account trying to initiate the activation (often a system account like SYSTEM or NETWORK SERVICE when triggered by a service) doesn’t have launch rights for that specific DCOM application (APPID), you get an activation error.
Access Permissions: Determines which users or groups can connect to and interact with an already running DCOM server process. If the calling user doesn’t have access rights, communication fails.
Identity: DCOM servers can be configured to run under a specific user account (the “interactive user,” the “launching user,” or a predefined account). If this identity lacks necessary permissions (e.g., file system access, network access), the component might fail even if DCOM permissions are correct.
Configuration Complexity: DCOM settings are managed through the Component Services administrative tool (dcomcnfg.exe) and directly within the Windows Registry. Incorrect configuration is a frequent cause of errors.

The error message we’re dissecting (“The application-specific permission settings do not grant Local Activation permission…”) points directly to a mismatch between the identity trying to launch the PresenceWriter component locally (indicated by LocalHost (Using LRPC)) and the permissions configured for that component’s APPID.

1.2 Deep Dive: Understanding “Presence”

In the context of communication and collaboration software, “Presence” refers to the status information that indicates a user’s availability and willingness to communicate. It’s the little dot next to a contact’s name in instant messaging (IM) clients, email applications, and collaboration platforms.

Common presence states include:

Online / Available
Busy
In a Meeting / In a Call
Do Not Disturb
Away / Be Right Back
Offline

How Presence Works:

Presence information is typically managed by a dedicated presence service, often part of a larger communication platform like Microsoft Teams, Skype for Business (formerly Lync), or historically, Office Communications Server (OCS).

Source Aggregation: The presence state is often automatically aggregated from various sources:
- Calendar: If a user has a meeting scheduled in Outlook/Exchange, their status might automatically change to “Busy” or “In a Meeting.”
- Application Activity: Being active in the communication client usually sets the status to “Available.” Inactivity might change it to “Away.” Being on a call sets it to “In a Call.”
- Manual Setting: Users can often manually override their status (e.g., setting “Do Not Disturb”).
Presence Server: A central server (or cloud service) collects this information, determines the user’s current definitive presence state, and stores it.
Subscription and Publication: Other users or applications (“subscribers” or “watchers”) can subscribe to receive updates about a specific user’s presence. When the presence state changes, the server publishes the update to all subscribers.
Integration: Presence information is often integrated into various applications (Outlook, SharePoint, custom apps) to provide context about colleagues’ availability directly within those workflows.

Relevance to PresenceWriter:

The term PresenceWriter strongly suggests a component involved in handling presence data, specifically in a way that relates to writing or persisting this data. Given the “Writer” suffix, the most likely connection is to the Volume Shadow Copy Service (VSS), which we’ll explore next. The presence data, potentially including user statuses, contact lists with associated presence, and configuration settings related to presence aggregation, might need to be backed up consistently.

1.3 Deep Dive: Volume Shadow Copy Service (VSS)

VSS is a crucial Windows technology that allows backup applications to safely back up files, even those that are open or locked by running applications (like databases or live system files). It achieves this by creating point-in-time snapshots, known as shadow copies, of a volume.

Key VSS Components:

VSS Service: The core Windows service that coordinates the activities of the other components.
Requestors: These are typically backup applications (e.g., Windows Server Backup, Veeam, Commvault, Acronis). They initiate the shadow copy creation process.
Providers: These components actually create and maintain the shadow copies. Windows has a built-in system provider (using copy-on-write), but hardware vendors can supply their own hardware-based providers.
Writers: This is the critical part for our discussion. VSS Writers are application-specific components that ensure application data is in a consistent state before the snapshot is taken. When VSS initiates a snapshot, it notifies all registered Writers. Each Writer then prepares its associated application’s data (e.g., flushing buffers to disk, temporarily pausing writes, finishing transactions) to ensure the snapshot captures a clean, usable state. Examples include the SQL Server VSS Writer, Exchange Writer, Registry Writer, and, pertinent to our case, potentially a PresenceWriter.

How VSS Works (Simplified Backup Scenario):

Backup Initiated: The Requestor (backup application) asks VSS to create a shadow copy of specific volumes.
Writer Enumeration: VSS enumerates all registered Writers on the system.
Prepare Snapshot: VSS notifies the Writers to prepare for a snapshot (PrepareForSnapshot event). Writers perform necessary actions to quiesce their application data.
Freeze: VSS instructs Writers to temporarily freeze application I/O operations (Freeze event). This window is very short.
Snapshot Creation: VSS tells the Provider to create the shadow copy.
Thaw: VSS immediately tells the Writers to resume normal I/O operations (Thaw event).
Post-Snapshot (Optional): Writers might perform cleanup tasks (PostSnapshot event).
Backup: The Requestor now uses the consistent shadow copy to perform the backup without interfering with the live applications.
Snapshot Release: Once the backup is complete, the Requestor informs VSS, and the shadow copy is typically deleted (unless intended for other purposes).

The Role of PresenceWriter as a VSS Writer:

Putting it all together, PresenceWriter is almost certainly a VSS Writer associated with a Microsoft communication platform (like Lync/Skype for Business Server components or potentially integrated services related to Teams). Its purpose is to ensure that data related to user presence (configuration, state databases, logs, etc.) managed by that platform is in a consistent state when a VSS snapshot is created, allowing for reliable backups of the communication system or the server it runs on.

Chapter 2: Synthesizing the Problem – Why the DCOM Error?

Now that we understand DCOM, Presence, and VSS, we can connect the dots:

VSS Operation: A backup process (or another operation utilizing VSS snapshots, like System Restore point creation) starts.
Writer Involvement: The VSS service needs to coordinate with all registered VSS Writers, including PresenceWriter.
DCOM Activation Attempt: To communicate with the PresenceWriter component (which might run in its own process or a shared service host process), the VSS service (or another related system process, often running as NT AUTHORITY\NETWORK SERVICE or SYSTEM) needs to interact with it via DCOM. This interaction often involves activating the component if it’s not already running in the required context. The error message specifically mentions Local Activation permission and LocalHost (Using LRPC), confirming it’s an attempt to launch or communicate with the component on the same machine.
Permission Denied: The DCOM configuration for the specific PresenceWriter component (identified by its CLSID and associated APPID) does not grant the necessary “Local Activation” permission to the user account that VSS is using to make the request (in the example error, NT AUTHORITY\NETWORK SERVICE).
Error Logged: DCOM logs Event ID 10016 in the System Event Log, detailing the component (CLSID, APPID), the user account denied permission (SID), and the permission type (“Local Activation”).

Therefore, the PresenceWriter DCOM error is fundamentally a permission misconfiguration issue within the DCOM framework. The system needs to activate or communicate with the VSS Writer responsible for presence data, but the security settings for that specific DCOM component prevent the requesting system account from doing so.

Is it Harmful?

While often benign if occurring sporadically (sometimes triggered by non-critical VSS operations), frequent occurrences, especially coinciding with backup failures, indicate a problem:

Backup Integrity: If the PresenceWriter cannot be properly coordinated during a snapshot, the backup of the presence-related data might be inconsistent or incomplete. While this might not affect the core operating system backup, it could compromise the ability to restore the communication platform’s presence functionality correctly.
System Noise: Even if not causing direct harm, floods of DCOM errors in the event log make it harder to spot genuinely critical issues.
Potential Instability: In rare cases, severe DCOM misconfigurations or the underlying issues causing them could potentially lead to instability in the related application or services.

It’s generally recommended to resolve these errors to ensure system health, reliable backups, and clean event logs.

Chapter 3: Diagnosing the PresenceWriter DCOM Error

Before attempting to fix the error, it’s crucial to gather the exact details from the Event Log.

Step 1: Open Event Viewer

Press Windows Key + R, type eventvwr.msc, and press Enter.
Alternatively, search for “Event Viewer” in the Windows search bar.

Step 2: Navigate to the System Log

In the left pane, expand “Windows Logs” and select “System”.

Step 3: Filter for the Specific Error (Optional but Recommended)

The System log can be noisy. To find the relevant errors quickly, click “Filter Current Log…” in the right Actions pane.
In the Filter dialog:
- Check the “Error” box under Event level.
- In the “” field, type 10016.
- From the “Event sources” dropdown, select “DistributedCOM”.
- Click “OK”.

Step 4: Locate and Analyze the Error Entry

Find an instance of the Event ID 10016 error that mentions PresenceWriter or has the specific CLSID and APPID you are investigating (if you already know them).
Select the error entry. The details will appear in the pane below (General and Details tabs).

Step 5: Extract Critical Information

From the General tab of the event description, carefully note down:

The CLSID (Class ID): A long string of letters and numbers enclosed in curly braces {}. This uniquely identifies the COM component (PresenceWriter in this case). Example: {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
The APPID (Application ID): Another long string in curly braces {}. This identifies the DCOM application configuration that governs the component’s permissions and activation settings. Sometimes, the APPID might be the same as the CLSID, or it might be different. Example: {yyyyyyyy-yyyy-yyyy-yyyy-yyyyyyyyyyyy}
The User SID: The Security Identifier of the user account that was denied permission. Common examples include:
- NT AUTHORITY\SYSTEM (S-1-5-18)
- NT AUTHORITY\NETWORK SERVICE (S-1-5-20)
- NT AUTHORITY\LOCAL SERVICE (S-1-5-19)
- A specific service account SID.
The Permission Type: Usually “Local Activation” or sometimes “Local Launch”. It could also be “Remote Activation/Launch” or “Local/Remote Access,” but for PresenceWriter triggered by local VSS, “Local Activation” is most common.

Having these four pieces of information (CLSID, APPID, User SID, Permission Type) is essential for applying the correct fix.

Chapter 4: Resolving the PresenceWriter DCOM Error

Resolving DCOM permission errors involves modifying system settings, either through the Component Services graphical interface or directly via the Registry Editor.

!! Important Prerequisites and Warnings !!

Administrator Privileges: You MUST be logged in as an administrator or have administrator credentials to perform these steps.
Backup the Registry: Before making any changes to the Windows Registry, it is highly recommended to create a backup. Open Registry Editor (regedit), go to File -> Export, choose “All” under Export range, give it a name, and save it somewhere safe.
Identify the Correct Component: Ensure you are modifying permissions for the exact CLSID and APPID identified in the Event Log error. Changing permissions for the wrong component can cause other system problems.
Grant Only Necessary Permissions: Do not grant “Everyone” full control just to make the error go away. Grant the specific permission (e.g., Local Activation) only to the specific user account (identified by the SID in the error).
Potential Lockouts: In some versions of Windows or for certain system components, the permissions in Component Services might be grayed out, and registry keys might be owned by TrustedInstaller. You will need to take ownership of registry keys first in these cases (explained below). Proceed with caution.

We will primarily focus on granting “Local Activation” permission to the specified user SID for the identified APPID.

Method 1: Using Component Services (dcomcnfg)

This is the preferred method as it’s less prone to accidental damage than direct registry editing. However, it may not always work if permissions are locked down.

Step 1: Find the Component Name (Optional but Helpful)

Open Registry Editor (regedit).
Navigate to HKEY_CLASSES_ROOT\CLSID\{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} (replace with the CLSID from the error).
Look at the (Default) value in the right pane. It often shows the friendly name of the component (e.g., “PresenceWriter”). Note this name.
Also, look for an AppID value in the right pane. Verify it matches the APPID from the error log. If it doesn’t exist here, the CLSID might serve as its own APPID, or the APPID reference is elsewhere, but typically it’s present.

Step 2: Open Component Services

Press Windows Key + R, type dcomcnfg, and press Enter.
If prompted by User Account Control (UAC), click Yes.

Step 3: Navigate to DCOM Config

In the left pane, expand: “Component Services” -> “Computers” -> “My Computer” -> “DCOM Config”.

Step 4: Locate the Component/Application

You will see a long list of DCOM applications. Look for the component using either:
- The friendly name you found in the registry (e.g., “PresenceWriter”).
- The APPID itself (sometimes the APPID is listed directly, though often enclosed in braces). Finding it by APPID can be difficult in this view.
If you cannot find it by name or APPID easily: This is common. The CLSID might map to an APPID that doesn’t have a friendly name listed directly here, or the component might not be explicitly listed under DCOM Config (some system components are managed differently). If you cannot find the specific APPID or a matching name easily, you will likely need to use Method 2 (Registry Editor). However, first, try searching the list carefully. Sometimes the APPID is the name displayed.
If you DO find the component: Right-click on it and select “Properties”.

Step 5: Modify Security Permissions (If Found in dcomcnfg)

In the Properties window, go to the “Security” tab.
Focus on the “Launch and Activation Permissions” section (since the error usually mentions “Local Activation”).
Select the “Customize” radio button (if it’s not already selected) and click the “Edit…” button.
- If the “Customize” option or the “Edit…” button is grayed out, you cannot change permissions here. You MUST proceed to Method 2 (Registry Editor).
In the “Launch and Activation Permission” window that pops up, click the “Add…” button.
In the “Select Users, Computers, Service Accounts, or Groups” dialog:
- Type the name corresponding to the SID from the error log (e.g., NETWORK SERVICE, SYSTEM, LOCAL SERVICE).
- Click “Check Names”. It should underline the name if found correctly.
- Click “OK”.
Back in the permissions window, select the user/group you just added (e.g., NETWORK SERVICE).
In the “Permissions for [User/Group]” list below, check the “Allow” box for “Local Activation“. (Ensure “Local Launch” is also allowed if that was the error, though often they are granted together). Do not grant unnecessary permissions like Full Control unless explicitly required and understood.
Click “OK” on the “Launch and Activation Permission” window.
Click “Apply” and then “OK” on the main Properties window.

Step 6: Check Access Permissions (Less Common for Activation Errors)

While still in the Security tab of the component’s Properties, look at the “Access Permissions” section.
If the error mentioned Access permissions (less likely for the standard PresenceWriter activation issue), repeat Step 5 but modify the Access Permissions instead, granting “Local Access”. Again, skip this if the error was specifically about Activation/Launch.

Step 7: Close Component Services

You can close the Component Services window.

Step 8: Monitor Event Log

Keep an eye on the System Event Log over the next day or after the next VSS operation (e.g., backup) to see if the Event ID 10016 error for PresenceWriter recurs.

Method 2: Using Registry Editor (Regedit)

Use this method if the permissions are grayed out in Component Services or if you couldn’t locate the component there. This involves modifying permissions on registry keys and requires extreme care.

Step 1: Identify CLSID and APPID

Ensure you have the exact CLSID and APPID from the Event Log error.

Step 2: Modify Permissions for the CLSID Key

Open Registry Editor (regedit) with administrator privileges.
Navigate to the CLSID key: HKEY_CLASSES_ROOT\CLSID\{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} (Use your specific CLSID).
Right-click on the key {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} in the left pane and select “Permissions…”.
Click the “Advanced” button.
At the top, you’ll see the current “Owner”. It’s often TrustedInstaller. Click the “Change” link next to it.
In the “Select User or Group” dialog, type Administrators, click “Check Names”, and click “OK”.
Back in the “Advanced Security Settings” window, check the box “Replace owner on subcontainers and objects”.
Click “Apply”. You might see a confirmation message; click “Yes”.
Click “OK” to close the Advanced window.
You are now back at the main “Permissions” window for the CLSID key. Select the “Administrators” group in the list.
Check the “Allow” box for “Full Control“.
Click “Apply” and then “OK”.
- (Self-Correction Note): We took ownership and gave Administrators Full Control primarily to allow Component Services (or subsequent registry edits) to modify the DCOM settings stored within or referenced by this key. Direct modification of binary permission values here is risky. The goal is to unlock the component for modification via dcomcnfg if possible, or to modify the APPID permissions next.

Step 3: Modify Permissions for the APPID Key

Crucially, DCOM launch/activation permissions are primarily governed by the APPID key, not the CLSID key.
Navigate to the APPID key in Registry Editor: HKEY_CLASSES_ROOT\AppID\{yyyyyyyy-yyyy-yyyy-yyyy-yyyyyyyyyyyy} (Use your specific APPID from the error log).
- Note: Sometimes the curly braces are not shown for APPID keys directly under HKEY_CLASSES_ROOT\AppID. Look for the string without braces if you don’t see it with braces. However, the standard path includes them.
Just as you did for the CLSID key:
- Right-click the APPID key {yyyyyyyy-yyyy-yyyy-yyyy-yyyyyyyyyyyy} and select “Permissions…”.
- Click “Advanced”.
- Change the “Owner” to the Administrators group.
- Check “Replace owner on subcontainers and objects”.
- Click “Apply”, then “OK”.
- Back in the main “Permissions” window for the APPID key, select “Administrators” and grant “Allow” for “Full Control“.
- Click “Apply” and then “OK”.

Step 4: Attempt Modification via Component Services AGAIN

Now that you (as Administrator) have Full Control over the relevant CLSID and APPID registry keys, go back to Component Services (dcomcnfg) and try Method 1 again (Steps 2-5).
Often, taking ownership and granting Administrators Full Control in the registry is enough to un-gray the “Customize” and “Edit…” buttons in the DCOM Config security properties for the component.
This is the SAFEST way to proceed after registry ownership changes. Let the Component Services tool manage the actual permission changes if possible. Add the required user (e.g., NETWORK SERVICE) and grant “Local Activation” as described in Method 1, Step 5.

Step 5: Direct Registry Modification (Use ONLY if Component Services STILL Fails)

WARNING: Directly editing the binary LaunchPermission or AccessPermission values is complex and risky. It’s generally discouraged. However, if dcomcnfg absolutely refuses to cooperate even after registry permission changes, this is the last resort for directly granting the needed permission via the registry. This step is usually NOT necessary. If you are at this point, double-check that you correctly identified the APPID and took ownership. Consider seeking expert help before proceeding.
If you must proceed: The LaunchPermission value (and AccessPermission) under the APPID key (HKEY_CLASSES_ROOT\AppID\{APPID}) stores the security descriptor in binary format. Modifying this requires deep knowledge of Security Descriptor Definition Language (SDDL) or using specialized tools/scripts. Manually editing the binary value is highly prone to error and could break DCOM functionality. Due to the complexity and risk, detailed steps for manual binary editing are omitted here. The recommended path after taking registry ownership is ALWAYS to try dcomcnfg again.

Step 6: Restore Ownership (Optional but Recommended Practice)

After successfully modifying permissions (ideally via dcomcnfg after Step 4), it’s good practice to restore ownership of the registry keys back to TrustedInstaller for system components.
Go back to the Permissions -> Advanced settings for both the CLSID and APPID keys.
Click “Change” next to the Owner (which is currently Administrators).
Type NT SERVICE\TrustedInstaller, click “Check Names”, and click “OK”.
Uncheck “Replace owner on subcontainers and objects” (unless you know you need to revert ownership recursively).
Click Apply -> OK.
You may also want to remove the explicit “Full Control” for Administrators if it wasn’t there originally, but ensure SYSTEM and other necessary default accounts still have appropriate permissions (usually Read).

Step 7: Reboot (Recommended)

Although not always strictly necessary, rebooting the system after making significant DCOM or registry permission changes can help ensure they are fully applied.

Step 8: Monitor Event Log

Check the System Event Log again after the reboot and subsequent VSS activity to confirm the error is gone.

Method 3: VSS Specific Troubleshooting

Sometimes, the DCOM error might be a symptom of an underlying VSS issue related to the PresenceWriter itself.

Check VSS Writer Status:
- Open an administrative Command Prompt or PowerShell.
- Type vssadmin list writers and press Enter.
- Look for PresenceWriter (or a similarly named writer related to your communication platform, e.g., Lync Server Writer, Skype Server Writer).
- Check its “State”. It should ideally be [1] Stable.
- Check the “Last error”. It should be No error. If there’s an error listed here, it points to a problem with the writer itself, not just DCOM permissions. Troubleshooting would then focus on the Lync/Skype/Teams application associated with the writer.
Restart Services: Restarting related services can sometimes clear transient issues:
- Volume Shadow Copy service
- COM+ Event System service
- The specific service(s) associated with PresenceWriter (e.g., Lync Server Frontend, Skype for Business Server Frontend, or related services). Use services.msc to find and restart these.
Check Disk Space: Ensure the volume hosting the operating system and the communication platform data has sufficient free space. VSS requires free space to operate correctly.

Method 4: Application-Specific Checks

If the PresenceWriter VSS writer shows errors or if DCOM fixes don’t work, consider issues with the related application:

Repair/Reinstall: Try repairing the installation of the communication platform (Lync/Skype for Business Server components, potentially parts of Office if Teams integration is involved). If a repair doesn’t work, a carefully planned reinstall might be necessary (ensure you have backups and understand the implications).
Check Application Logs: Look for errors within the specific application’s event logs (often found under “Applications and Services Logs” in Event Viewer) that coincide with the DCOM errors.
Updates: Ensure the communication platform software is fully updated. Patches often fix VSS writer and permission issues.

Method 5: System File Checks

Corrupted system files can occasionally cause DCOM or VSS problems.

Open an administrative Command Prompt or PowerShell.
Run System File Checker: sfc /scannow
If SFC finds and fixes issues, reboot. If it finds issues it cannot fix, run DISM:
- DISM /Online /Cleanup-Image /CheckHealth
- DISM /Online /Cleanup-Image /ScanHealth
- DISM /Online /Cleanup-Image /RestoreHealth
Reboot after running DISM commands and try sfc /scannow again.

Chapter 5: Preventing Future Occurrences

While resolving the current error is the priority, consider these steps to minimize recurrence:

Keep Systems Updated: Apply Windows Updates and updates for your communication platforms (Lync/Skype/Teams/Office) regularly. Patches often include fixes for known permission and VSS writer issues.
Monitor Event Logs: Regularly check System and Application event logs for recurring DCOM errors or VSS warnings. Early detection can prevent larger issues.
Understand Application Requirements: When installing server applications like Lync/Skype for Business, pay close attention to documentation regarding required service accounts and permissions. Proper setup from the start can prevent many DCOM issues.
Least Privilege Principle: While fixing this error requires granting specific permissions, maintain the principle of least privilege elsewhere. Avoid overly broad permissions (like granting “Everyone” rights).
Standardized Builds: In enterprise environments, using standardized server builds and deployment processes (like Group Policy or Desired State Configuration) can help maintain consistent DCOM configurations.

Chapter 6: When Standard Fixes Fail

If you have meticulously followed the steps above, particularly ensuring you’ve identified the correct CLSID/APPID and user SID, and the PresenceWriter DCOM error persists, consider these possibilities:

Incorrect Component Identification: Double-check the CLSID/APPID and SID from multiple instances of the error log to ensure consistency.
Multiple Underlying Issues: The DCOM error might be one symptom of a more complex problem involving VSS, the specific communication application, or even storage subsystem issues.
Third-Party Software Interference: Antivirus software, security hardening tools, or other third-party applications could potentially interfere with DCOM or VSS operations. Try temporarily disabling them (in a controlled manner) for testing.
System Corruption: Deeper system file or registry corruption might exist that SFC/DISM couldn’t fix.
Complex Environment: In highly complex environments (e.g., multi-server Lync/Skype deployments, complex federation), the interactions might be more intricate.

In such cases:

Consult Microsoft Documentation: Search the Microsoft Learn site and Knowledge Base for the specific CLSID, APPID, and error context.
Community Forums: Search or post (with detailed error information, CLSID/APPID, and steps already tried) on forums like Microsoft Q&A, TechNet (archive), or relevant communities.
Professional Support: Engage Microsoft Support or consult with an IT professional experienced in Windows Server administration, DCOM, and the specific communication platform involved.

Conclusion

The PresenceWriter DCOM Event ID 10016 error, while initially cryptic, typically boils down to a permissions issue where a system service (often related to VSS operations like backups) is denied permission to activate the VSS Writer component responsible for handling Microsoft presence data (from Lync, Skype for Business, etc.).

Understanding the roles of DCOM (for component communication and activation), Presence (user availability status), and VSS (for creating consistent backups via Writers) is key to diagnosing the problem. The resolution usually involves carefully identifying the specific CLSID, APPID, and user SID from the System Event Log and then using either Component Services (dcomcnfg) or, with caution, the Registry Editor (regedit) to grant the necessary “Local Activation” permission to the correct user account for the identified APPID. Taking ownership of registry keys may be required before permissions can be modified.

While often not critically harmful on its own, resolving this error ensures the integrity of backups involving presence data, reduces event log noise, and contributes to overall system stability. By following the detailed diagnostic and resolution steps outlined in this article, administrators and power users can effectively tackle the PresenceWriter DCOM error and gain a deeper understanding of the intricate workings beneath the Windows surface. Remember to proceed methodically, back up critical data and the registry, and grant only the necessary permissions to maintain a secure and stable environment.