This article uses a particular Windows Event ID 10016 error caused by Windows SharePoint Services 3.0 on SBS Server 2008 as an example, but can be used to troubleshoot other 10016 (DCOM) errors.

Event ID: 10016
Level: Error
Description:
The application-specific permission settings do not grant Local Activation permission for the COM Server application with CLSID {61738644-F196-11D0-9953-00C04FD919C1} to the user NT AUTHORITY\NETWORK SERVICE SID (S-1-5-20) from address LocalHost (Using LRPC). This security permission can be modified using the Component Services administrative tool.

1. Find name of the offending COM application:
Start > Run > regedit
Expand HKEY_CLASSES_ROOT\CLSID\{61738644-F196-11D0-9953-00C04FD919C1} or just search for the ID (61738644-F196-11D0-9953-00C04FD919C1) in regedit (F3)
Make a note of the “Default” value – IIS WAMREG admin Service

2. Fix the permission problem:
Start > Run > dcomcnfg
Component Services > Computers > My Computer > DCOM Config
IIS WAMREG admin Service > Properties
Double check that Application ID matches CLSID in the 10016 error
Security Tab > Launch and Activation Permissions > Edit > Add
Add the account mentioned in 10016 error (NETWORK SERVICE) and grant the equired permissions (Local Launch and Local Activation).

Windows Small Business Server (SBS) 2008