I have the exact same problem. On Tuesday, Avast updated and said that is needed the computer to restart. Everytime I restart it, it gets to Loading Persoanalized Data, then Blue Screen saying that fssfltc_tdi.sys unloaded with cancelling pending operations. I tried to go into Safe Mode, but it freezes up. The only way that I can even get into the system is through the recovery console, and you can not do much from there.