DCOM event error 10009

OS = Windows Server 2003
Event ID = 10009
Patch Level = Current
Error Message = DCOM was unable to communicate with the computer xxxx using
any of the configured protocols.

Notes:
The error message occurs about every hour. The message pertains to several
retired workstations that were previously on the local network. This is a DC
and Exchange is not loaded on this box.

Does anybody know of any service that Microsoft runs that would query
retired machines?

I have applied all recommendations that apply in article ID 245197
http://support.microsoft.com/default...b;en-us;245197

Thanks to all.