I just updated my free verison of avast and Now windows 7 has a problem in my action center saying Windows did not find antivirus software on my computer
Before I updated to verison 8 free
I didn’t have this problem
Is there a fix without turning off messages about virus protection 
Have you rebooted since the install ? Can you try running the repair and reboot when completed.
Yes I did that and still no change
If it was an install of 8 over the top of 7 then I’d suggest uninstalling then run the removal tool for all versions of avast you have ever installed then re-install a fresh copy of avast 8.
“NOTE” download new avast 8 and the removal tool and save before uninstalling current copy.