Could be windows updater doing it's job, sometimes the updates overwrite system files (pretty logical), so i suggest you either disabling automatic updates or updating to the latest sp3 and latest hotfixes.
In case it doesn't work, would be nice if you share what windows release you are using.
gtfo zodiac
And yeah, it DOES work. (even when I reboot from safe mode to normal mode)
Though, when I turn off the PC for the night, and then turn it on the next morning, accel is again ENABLED.
So accelfix.exe only works temporarely for me, which is kinda strange, and I want it to work permanently.
In case it doesn't work, would be nice if you share what windows release you are using.
Source