In the link provided, you will find an extensive list of COM Error Codes and brief description of each.
The list contains:
1. COM Error Codes
2. Miscellaneous Error Codes
3. OLE (Object Linking and Embedding) Errors
4. Windows Based Enterprise Management (WBEM) error codes
5. The Win32 Error Codes for ADSI.
6. ActiveX Data Objects (ADO) Runtime errors
http://kenbase.googlepages.com/COMErrorCodes.htm
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