How do I change file type of all .exe files?

I was playing around on my computer with regedit.exe, I found file type .exe and clicked it. There were two files (looks like a piece of paper torn in half with red letters "ab" on it), I right clicked the first, went to modify, and changed the value from "exefile" to "C:\Users\Stewy\Pictures\green.ico" just to see what would happen. Then, I logged off and back on, and all my .exe files looked like the default file icon (just a piece of paper), and when I clicked them, nothing happened. I only got on the internet through a shortcut to a website I had previously made. When I right-click the .exe files, and go to properties, then the details tab, it says "Type: C:\Users\Stewy\Pictures\green.ico", how can I change it back to" exefile" if I can't open regedit.exe?

Thank you,
Stewy

LOL - that was good idea stewy.

Check if you can enter regedit by command line. If you were able to start a browser by using a shortcut, you could also start cmd.exe in this way, or maybe manage to create a shortcut to regedit directly. Booting into safe mode may help too, or a system restore if you have any recent points saved.

By the way, to change the icon of all executables, you should go to HKEY_CLASSES_ROOT\exefile\DefaultIcon\(default)
The value you changed is merely a "pointer" to another registry key. It basically means "for files with a .exe extension, look into the key named ......... (exefile by default) and find the details there". By removing that exefile link, Windows didn't knew what .exe files were giving that error.

Whatever, thank you anyway.