Adwords editor recently prompted me to upgrade so I did. Then the program stopped working and hasn’t worked in a week. I finally spent a few hours yesterday and today to troubleshoot the issue. I tried uninstalling and reinstalling. I tried uninstalling, cleaning the registry, and then reinstalling. Still no dice.
Finally I uninstalled and looked in the Google directory on my c: drive† C:\Program Files\Google\ and sure enough there was a ‘Google AdWords Editor’ directory full of files. When I deleted this folder and reinstalled again the program started working.