When starting regedit then it go to the registry-location, which it displayed last time before it was closed.

This behavior can be disabled with the following steps:

1. Run Regedt32 (Not regedit) which enables you to set security for registry keys
2. Go to this location:

   [HKEY_CURRENT_USER \Software \Microsoft \Windows \CurrentVersion \Applets \Regedit]
   

3. Find the entry "LastKey"
4. Select the entry and from the menu select Security / Permissions
5. Deny Full Control to the currently logged in user

More Info MS KB244004

Related Let regedit remember your registry favorites

Credits ntcanuck.com/tq