Disable Rapid Release in Mail Security if you intend to update definitions through Symantec Endpoint Protection version 11.x or Symantec AntiVirus Corporate Edition.
Configure your other antivirus programs to exclude certain folders from scanning. If another antivirus program scans the Exchange directory structure or the Mail Security processing folder, it can cause false-positive threat detection, unexpected behavior on the Exchange server, or damage to the Exchange databases
For information about how to prevent Symantec Endpoint Protection version 11.x or Symantec AntiVirus Corporate Edition from scanning the Exchange directory, go to the following Symantec knowledge base article
If you have Symantec AntiVirus™ Corporate Edition or Symantec Endpoint Protection (SEP) version 11.x installed on the same computer as Mail Security, configure Symantec AntiVirus Corporate Edition or SEP version 11.x to perform definition updates. For Exchange Serverversion, you must also configure Mail Security to perform definition updates. You can also use LiveUpdate Administrator to perform definition updates for both the products.