Hey all, I've been lurking in the forum for quite some time, relying on others to ask the questions I need answered.  Today I've encountered an issue I've not seen discussed on this forum (or at least not applicable to my environment), affecting several machines in an enterprise environment.  

Issue seems to reside with emails that contain file attachments. Emails that did not contain file attachments opened promptly.  Checking Event Manager under the SYSTEM portion, we found several of the following:

Timeout (30000 milliseconds) waiting for a transaction response from the Symantec AntiVirus service.

Checking for similarities on other machines, I found that this appears to stem from a corrupted dat file from 2-3-2010 rev 4 for Symantec Anti-virus.  When we attempt to LiveUpdate, the process completes, appearing to have downloaded and install new definitions, but the version does not update in the SAV screen, nor has anything changed.  A look in the Documents and Settings\All Users\Application Data\Symantec\Symantec AntiVirus Corporate Edition\7.5\ folder shows a few folders containing updates, the most recent one (the last day updated) contains numberous *.9## files, all of which are only a few KB in size, compared to the more normal looking definitions in the previous folders.