It's not FOS issue. Directly visit Fortiguard server will meet same
issue, for example: https://www.fortiguard.com/fos/43545, see the error
page also. We've submit the mantis bug #405649 which should be increase
to S2
IPSE version 3.300 and later (for FOS 5.4) fixed this P2P category
blocking issue.The reason is pseudo IM/P2P rules attributes are loaded
from IPS/AppCtrl databases, but the IPS engine does not encode it
correctly for FOS, so FOS get empty attributes...