They put out a Windows 7 “security” update in February that caused Corel Video Studio to not load. It actually had something to do with Win 10. I removed the update and shutdown all MS updates.
Win 7 is supposed to be supported into 2020, but I think MS is going to stop support long before that.
I do think MS is messing with the Win7 Microsoft Security Essentials updates.
Sometimes the current definitions load fine and at other times, they stall out. That only started about 6 months ago.
Now, I find the best way is to manually download the virus definitions file and physically run it.
I tried Win10 on an extra desktop hard drive and hated it. I have no intention of switching to it.