I just got an error (not the eng_imgrepository.dll error) and was kicked out of a dungeon. I didn't write down the error # but it was a very large dialog box and it said something about game guard having to shutdown and I have to reboot. I'm pretty sure it mentioned something about hacks but that can't be right as I'm just running the default client (no UI mods or anything).

I have no AV running and haven't had problems for the last month or so up until now.