Answer
GMS Anti-Virus actions and the rejection of banned attachments were incorrectly using the same Actions. the result of this was that any attachment types which were set as disallowed could, dpending on the GMS Anti-Virus settings, have been redirected to a specified account, or allowed through to the recipient.
The actions for these two features are now set independently of each other and you can now quarantine, accept or reject GMS Anti-Virus or banned attachments independently of each other.
See Also:
Keywords:VPP reject attachext attachment extensions reject GMS Anti-Virus Virus checker GMS Anti-virus anti virus antivirus