Event ID : 1005

Issue: GC on network is not responding.

Event Source: MSExchangeSA

Cause :
This behavior can occur if the .dll listed in the event ID message is either absent or corrupted.Event ID 2059 and 1005 Messages Occur and System Attendant Is Unable to Start .

Description : We have observed that GC on network is not responding, the possible reason may be:This behavior can occur if the .dll listed in the event ID message is either absent or corrupted. The file name.dll is required but cannot be loaded, error 'c007007f'

Action Required :To resolve this behavior, replace the absent or corrupted .dll with the appropriate .dll that is available on the Release to Manufacturer CD-ROM, or the .dll that is available on your latest service pack. These files are typically located in the Exchsrvr\Bin folder.

Ref. Link : http://support.microsoft.com/kb/295620/en-us