I have a feeling it's AVG. You need to figure out a way to rip it out of the unit somehow..
Boot up in Safemode there's an option menu to do so I believe when you hold shift when you press 'Restart'.
Try to uninstall it in SafeMode, if it doesn't uninstall that way, then maybe delete the folder it's in.
Update all the things Windows wants, then re-install AVG if you really want it back. Though I have a feeling it may conflict with the update.
OR
Boot up (maybe need to in safemode), hide the updates that're failing and ignore them.
I'd rid of AVG though. Seems too much of a hassle to me. Your unit already has Windows Defender which should be more than sufficient. But yeah.. ;d
P.S. Are you sure your screen replacement was done properly? I am anything but a 'purple' 'elf.'.. ;d
❤