Log
From ModWiki
You can get the Log.txt file from the following location: /Users/"your username"/Library/Preferences/Ableton/Live 8.x.x/Log.txt
or if you're on PC: Windows XP/Vista/7 C:\Documents and Settings\"your user name"\Application Data\Ableton\Live\Preferences
Windows 7 C:\Users\"your user name"\AppData\Roaming\Ableton\Live 8.x.x\Preferences