Nobody can tell you anything without exact system info or other technical details. Start by checking your harddrive for errors and make your security behave so files don't get damaged.
The .old suffix makes me think you may have a previous installation of Windows left on your hard drive after an update. Maybe that's messing up the installation of AE.
Are you still facing this problem? If not, let us know how you solved it. If so, please let us know so we can assist you further.
Yes I'm still having the same issue. I've tried uninstalling and installing it again.
I've done a full virus and system scan on my computer and had anything fixed.
I think I might uninstall, delete an files that are related to Adobe After Effects and go from there. Let you guys know how I went. It looks like no one knows I see.
MY SYSTEM SPECS:
i7-4810MQ CPU @ 2.8GHZ
So I deleted old files from 2013 and 2014. The program now works!
I hope this helps anyone else if this happens again!