Some places say to go to HKEY_USERS\.DEFAULT\Control Panel\Keyboard but really you need to change it to 2 at HKEY_CURRENT_USERS. Try that.
Microsoft also gives a solution with a small script you can do:
Link Removed
* Try to turn off the default numlock setting in your BIOS. That way, the OS will turn it on.
* Another method that helped some:
1. hit NumLock to have light ON
2. press "Ctrl + Alt + Del"
3. click Log Off from the drop down menu
4. log back in and reboot for the test
If this doesn't do it, then repeat above, but do a shutdown with it on
and restart.
Don't use the method through start menu. This is reported to have
reset the startup of numlock.
* I posted this above but here's a clearer version:
- Click...