.:Executables ran as a notepad file:

Hello, when trying to remove a nefarious trojan from my PC and trying to edit a .exe file in notepad, I created a hellspawn of an error on my OS: in my registry, in HKEY CURRENT USERS / software / microsoft / windows / current versions / explorer / fileexts / .exe, I now have these two keys: application: notepad.exe and in the openwithlist subfolder: a = notepad.exe.

How do I revert to opening .exe files normally? Thanks!