http://bugs.winehq.org/show_bug.cgi?id=17662
--- Comment #8 from Dmitry Timoshkov dmitry@codeweavers.com 2009-05-11 02:49:26 --- That means that you had an old ~/.wine prefix, without mountmgr.sys service in the regsitry. The question is why running winecfg doesn't force the prefix update while running notepad does.