I installed 1.6.1 upgrade, message asked to uninstall previous version writing that all old libraries will remain untouched but the new installation deleted all my arduino folder library included (luckly had make a backup before). I misunderstood something?
When the IDE get uninstalled, it deletes the content of c:\program files\arduino (or something like that).
What remains untouched is your sketchbook and its content.
However, if you're coming from IDE 1.0.x, we have changed the location of the preferences file, so the newer IDE is using the default sketchbook location, which is C:\Users\username\Documents\Arduino
Yes I was coming from 1.0.5.
Thanks for your reply.