I have encounters a problem with mission control.. Everything was fine, then suddenly it has put folder windows in-between spaces. I clicked on my HD and the window didn't open, I clicked on my DropBox folder, no window opened. I then flicked between spaces, to see if the folder was in another space. The folder windows, momentarily appear as the mission control flips between spaces.. HELP! How have I close these windows; Or how can I do a full reset not the OS does this open things as they were things when you reboot?