Change file extensions in Windows 7

I am new to Windows 7, having used (and loved) XP for several years now. With XP, I’m able to drag a song snippet to the desktop and change the extension from .mp4a to mp4R (creating a new ringtone for iPhone). However with Win7 I can’t figure out how to change the extension. I’ve gone into control panel settings to uncheck “hide all known extensions” but it still won’t show. Even placing the snippet into a folder won’t let me change the extension, just the name.

Any help?
Apologies if this has been covered…

If you change the “Hide extensions for known file types” setting in one folder, it won’t apply to all folders unless you click the “Apply to Folders” button afterwards. Do that, and you ought to be able to see extensions after that.

It’s been applied to all, and computer rebooted just in case. Still nothing.

Weird, that ought to do the trick. Try running the fix-it tool found in this kb article (click the Fix It button about 1/4 down the page) and see if that clears it up.

Once you get it working, the way Win7 handles them is better. When you go to rename a file, the extension won’t be highlighted, making it easier to just change the name. I love it.

To the OP … are you trying to see the file extensions in Windows Explorer? Just click “Tools” in the top menu of Windows Explorer, go into the “View” tab, uncheck “Hide extensions for know file types”, and click the “Apply to Folders” button. Should work. Once you see the file extensions you can change them to whatever you like.