I installed the Windows 10 update on the twenty-fourth of October this year. The first thing that I saw was a Rundll32 error or something. Next, OneDrive stopped working. A few days later, GTA V stopped working. Now, the Start Menu doesn't work, meaning if I click the Windows logo, it'll prompt me to sign out to "fix" the problem. So, I tried to go back to Windows 8.1 (64-bit flavor) one week after the update-a quarter of the deadline to update. Instead, apparently "the files that were needed to take you back were deleted", even though they're in plain sight according to file explorer-$SysReset, $WINDOWS.~RT, and $Windows.~WS I believe. Is there anyway that I can go back, or do I have to cough up another $90 to go back? Thanks in advance to anyone who helped.