I’m slipping up. Post #25 was also meant for hsmomx3.
I am experiencing the same problem you are, and it just started on Dec. 22.
If I do a google-search on “Dropper.Generic.THT”, four items are returned. In all four cases, the anti-virus software being used is AVG. I think the odds of that are extremely low, much too low to be a coincidence. Maybe I am barking up the wrong tree, but I’m very suspicious.
I wonder if AVG itself has been hacked. Did your problems begin happening soon after an AVG update? I believe mine were.