We recently upgraded to Server 2012 R@ and SMSMSE 7.5.1.83.  Now even once in awhile the Mail Security for Microsoft Exchange shuts itself off.  Whenever is shuts off, we get hit will all sorts of spam emails.  This seems to be the only service that won't automatically restart.  It is set to start automatically.

What can I try to ensure this service will not shut itself off?

Thank you!!

This is something that you need to bring with Symantec forum to get insight of MSME related issues...

Hi,

Can you start the service manually? Is there any error logs for this issue?

If the service can't be started manually either, please provide the error description for further troubleshooting. I think the issue is related to Symantec Mail Security for Microsoft Exchange. We can also ask a question in Symantec forum for more help as what Amit said.

Additionally, please upgrade your Exchange 2013 to the latest service packs to have a try. Third-party transport agents cannot be loaded correctly in Exchange Server 2013:

https://support.microsoft.com/en-us/kb/2938053

Re