reset default preferences ableton live windows 7
Windows 7 Start Button
Show Hidden Folders in Windows 7
To re-set your ableton live preferences, you may need to show hidden folders in your windows 7 system.
To do this:
Click on your start button in the lower left corner
in the search bar type "Folder Options"
Hit Enter (or click on the top folder that appears from the search)
Go to "View"
Scroll down and enable the "Show hidden files and folders" and click "apply".
How to reset preferences in Ableton Live for Windows 7
C:\Users\your user name\AppData\Roaming\Ableton\Live 8.1.1\Preferences
C:\Users\your user name\AppData\Roaming\Ableton\your version of live\Preferences
Delete the Preferences.cfg file for the version you are trying to open, and re-open Live.
If you can't find it you might need to make your folders "not hidden"