I have just moved from Symantec AV and Antispam to Sophos PureMessage, which manages AV and Antispam scanning of messages via our exchange server.
Our exchange server connects direct to our ISP via ADSL, with an allocated IP address. All emails come straight to our server, and leave from our server. So no upstream or downstream servers that relay messages.
Is there a way or anything to check how/why messages would slip past PureMessage completely and not process any SMTP messages at all?
Have tried completely removing Symantec and Sophos (including via regedit of all their entries of 'Symantec' and 'Sophos') and reinstalled Sophos. Still to no avail.