Wow, a very nice answer very quickly -- impressive. Unfortunately neither of the two router layers this computer is behind has the capability to block incoming connections by remote IP, but definitely a reasonable suggestion. I do use RDP (very handy; sole reason to get Windows Professional over Home for me), so I don't want to close that port. I could change the port number, but that's only a temporary solution.
Is there a way to configure Malwarebytes to not pop up notifications for this kind of protection? It looks like adding this (malicious) IP to my "Allow" list would achieve th