I opened Ableton Live (6 LE - Mac Version) last night and none of the instruments or effect presets were in the Library pane. The instrument and effect unit names were there, but when I click on the arrow to expand the tree view...nothing appears.
I moved the application to the trash and inserted my Live DVD to reinstall, figuring that would fix it, but had no success.
I reinstalled the impulse live pack and that fixed impulse, but I didn't find a simpler or effect preset pack to install.
Why would all the instrument and effect presets disappear?
How do I get them back?
How do I perform a clean reinstall of Live?
Update: I contacted Ableton support and they indicated that the only way to fix this is to update to a newer version. Of course, they offer free upgrades from one LE product to the next online.
I found an additional preference file in user/libraries/preferences/ableton and deleted it, then reinstalled Live 6 LE from disc. It worked fine after that.