You can remove it with your registry editor. First, be certain you are deleting the correct file. In the unfortunate event that you delete the wrong one, iIt can be a bigger problem than you started with!
Press start, go to run. type REGEDIT. A page similar to windows explorer pops up.
click the plus sign to expand at HKEY LOCAL MACHINE. Find your file. Right click and delete.
If this still denies you access, you need to change permissions. Right click file select PERMISSIONS. Change to allow full access, then delete.
Good luck!