I figured out how to make LOGic ignore script errors from DX Summit advertisers, then I got a virus
. I am 99.9% sure it is from a DX Summit advertiser, as I was running nothing else at the time. It was one of those fake virus scanners that totally takes over your system.
My Windows Security Essentials had failed to update for some reason.
I was able to get rid of it by running a bootable version of Windows Defender, then running System Restore. Association with the .EXE file extension had been lost, but I was able to run System Restore by opening the \Windows\System32 folder and double-clicking RSTRUI.EXE