Figured out how to use the ForeFront built-in commandline scanner to scan for virusses. This possibly also works for the Home version of ForeFront, Security Essentials.
Application Path: C:\Program Files\Microsoft Security Client\Antimalware\MpCmdRun.exe
Parameters: -Scan -ScanType 3 -File "%s" -DisableRemediation
Thread Priority: Normal
Return Value: 2
Hide Scanner Application Window [Checked]
Side note If you do use ForeFront on your AMS server I would exclude the following directories from being scanned by the Real-Time scanner: \config, \scan & \temp. Otherwise this will cause ForeFront to "block" the file and this will in turn cause some issues in AMS.