Outlook folders are duplicated and cannot be deleted, how can I fix?

This morning when I powered up my PC and began Outlook 2003, 2007, 2010 all my personal folders had disappeared. Panic was starting to set in and I tried everything imaginable until I madly closed and restarted the program, when thankfully my folders were back. Unfortunately for some of these folders but not all I now have duplicates that I cannot get rid of.