How to delete old provisioning profiles from appearing in Xcode

I believe that if you are in XCode, and you go to Window and then Organizer, you will see a list of the profiles on your device. If there are there, you can highlight one, and hit the minus button. You may have to unplug your device, or reset it. It doesn't seem to work perfectly. You can also go to ~/Library/MobileDevices/Provisioning Profile/. in a terminal and RMove them.

I am having this exact same problem. The files in the /Users/[your_name]/Library/MobileDevice/Provisioning Profiles folder, are only those .mobileprovision files that were assigned to specific serial numbered devices. It's not the information embedded within Xcode that we want to delete, which just won't go away. We desire to delete these old profiles from within Xcode because we believe the list of identical named profiles is causing some of our unreliable sync problems on our dev team. Thank you for any ideas...

I had a similar problem awhile back. I wanted to delete a provisioning profile but when I tried deleting it from Organizer, it never went away and stayed in Organizer and the build settings. What I eventually figured out was I had used this profile for testing on a device and I guess it won't delete if xcode still thinks its being used for a device.
So what I did was plug my test device in so Organizer recognized it, went into the Preferences.app (Settings) on my iphone and deleted the profile off the device. Then when I tried deleting it again in Organizer, it finally went away.