Basically Microsoft is saying it’s OK to have file-based antivirus software on Forefront Edge products as long as the exclusions listed in the TechNet article are followed. These products are (at of the date this blog was created):
I vaguely remember a few years ago Microsoft’s stance was no file-based antivirus software on any “firewall” product. The reason was the more software you have on an edge product the more exploits are available. I can’t remember if I heard that online, from someone, or at the Forefront Airlift. Either way Microsoft’s stance today is file-based antivirus on Forefront Edge products are OK as long as the exclusions are followed.