I don't uninstall and it happens wether I manually install or automatically upgrade and on more than one PC. It has happened about the last half dozen times I have upgraded to the newest version. One Win7 PC and one running Vista. Oh, I guess I should clarify: this is not my Library Views disappearing but, when I go to "load" a view for a smartlist or playlist say, all my custom saved views are gone (good thing I have a backup copy). Sorry, if that wasn't clear.