I wanted to add a local folder to a custom library. That was not possible, because I received the following error message: This folder cannot be included because it is on a removable device. c:\Users\####\AppData\Local\opera\opera 10 Preview\mail\store This error is definitively wrong, because you can clearly see, that the folder isn't on a removable drive.I tested some other folders, none of which triggered that error. So I thought about what was so special about that opera folder.I remembered, that I simply copied that folder over from Vista, so maybe Windows 7 got confused by some permission- /security- / ownership-settings, which also got copied.So I took ownership of that folder (including replacing owner on subcontainers), and after that Icould add that folder to my library.