All downloads end up getting a corrupted file error

I upgraded my system from Windows 8 to 8.1, and right after that, I started having problems wherein every time I download something, even an update, ended up getting a corrupt files error. Anti virus and Windows updates included. I tried downloading a new browser to see if it works and it still gave me the same problem. Could it be a hardware related issue? I'm baffled, please help.
