This problem can occur for many reasons. This page provides some of the more common causes of this problem and links to specific documents to use to troubleshoot and resolve the problem.

Corrupted virus definitions

Virus definition corruption can occurs when you have Symantec Mail Security and another Symantec product updating virus definitions on the computer. For details see the following article: Configuring LiveUpdate when Symantec Mail Security for Microsoft Exchange and Symantec AntiVirus Corporate Edition or Symantec Endpoint Protection are installed together.

For information on how to repair already corrupted virus definitions, read The Exchange server is beeping, and / or you are getting the following SMSMSE events: 110, 168, 68, and 167, in Windows Application Event log.

Exclusions for Symantec Corporate Edition not set correctly

For details on setting up exclusions see the following article: Configuring exclusions when Symantec Mail Security for Microsoft Exchange and either Symantec Endpoint Protection or Symantec AntiVirus Corporate Edition or any other antivirus are installed together.

Real-time blacklist problems (Exchange 2000/2003)

Symantec Mail Security for Microsoft Exchange supports the use of real-time blacklists (RBL). An RBL is a list of mail servers that are known to pass spam. Symantec does not provide RBLs; to block by RBL, you must subscribe to third-party RBL providers before you configure Symantec Mail Security.  See the following article for more details:  Email stops flowing or is very slow when Symantec Mail Security 5.0 for Microsoft Exchange or Symantec Information Foundation Mail Security 6.x for Exchange running on Exchange 2003 is enabled.

Too many scan threads

Symantec Mail Security can be configured to use more scanning threads than the Exchange server's hardware can handle. See the following article for details: Exchange mail flow is slow and you notice many instances of SAVFMSESP.EXE (especially on computers with hyperthreaded CPUs).

Issues with LDAP email lookups

Mail flow is very slow or stops entirely when a content filtering rule for Symantec Mail Security for Exchange with a user condition is enabled.

Problems with blank subject line content filtering

Enabling the Blank Subject and Sender Content Filtering rule causes disruption to the Microsoft Exchange mail flow