Server Anti-Virus Software Issues This article outlines reported issues when deploying a stand alone Server-based Anti-Virus product (such as Norton Anti Virus and McAfee Anti Virus) along side Mailsite in addition to any email gateway anti-virus product or MailSite's integrated virus scanner. These adverse consequences may occur if the Server based Anti Virus software is set to scan the BOX directory.

1. The email message is no longer downloadable via IMAP:
   
   This issue can arise when the Server Anti-Virus has disinfected and remove the attachment from the message but has left the message still conforming to the RFC standards. This seems very harmless but there is a Stream on the .MSG file that caches the information regarding to the message content for more efficient access via IMAP. If the message is modified by the Anti Virus product then the caching information is no longer valid. This can prevent the message being downloaded via IMAP and in some cases POP.

2. Error log reports of Error 32(file locked):

   This arises when a client opens their mailbox via IMAP or POP and tries to view their mail but at that moment there is an exclusive lock on one of the messages by the Server Anti-Virus product scanning the message for a virus. This will lead to 'Error 32' messages in the log files and in some cases also within the email client.

   The above list is not necessarily all inclusive of the symptoms that may caused by simultaneous access of the Mailsite message store (commonly referred to as the BOX directory) .

Recommendation:

If it is deemed necessary to run a stand alone Server Anti Virus product on the Mailsite server then:

1. MailSite Systems strongly recommends excluding scanning of the Mailsite BOX, SPOOL and AVG directories.
2. If the above is not an option, then make sure you utilize the "delete" or "quarantine" options instead of the "disinfect" option.

For customers who are running AVG (integrated into Mailsite) Rockliffe recommend that you disable scanning of the BOX and SPOOL directories. AVG will block emails at the SMTPRA level and this will provide the protection to the SPOOL and BOX directories.