Note - these steps are only for SMSMSE 7.5.2 or newer. If you are having issue with a version prior to 7.5.2 please refer to http://www.symantec.com/docs/TECH233744
You see that the Update Status in Symantec Mail Security for Microsoft Exchange shows "Rapid Release Update was unable to complete successfully due to an FTP error". What is causing this problem?
Symptoms
Rapid Release runs either manually or scheduled.
The problem is with either name resolution on the proxy, or with the proxy itself.
Various solutions exist, depending on the exact cause of the problem.
If the proxy cannot resolve "ftp.symantec.com":
If the Exchange Server fails to connect to the proxy over ftp:
If the above does not describe the problem with Rapid Release definitions, please have a look at this document:
'Rapid Release updates crash, report an error code of 0 or stay stuck at "Running"'
http://www.symantec.com/docs/TECH90895
Technical Information
One way of testing where the issue is, is to open a DOS box on the Exchange server and try to connect to ftp.symantec.com