Outlook Error - Cannot start Outlook, can't open set of folders and it says outlook.pst is in use and can't be accessed.


  • In the past couple of weeks, my husband has been getting this error:  I marked this public so that hopefully you can take a peek at the error my husband printed out.  Basically, it says, "Cannot start Microsoft Office Outlook, Cannot open the Outlooks window.  The set of folders cannot be opened.  The file c:\users\morgan\AppData\local\Microsoft\Outlook\Outlook.pst is in use and cannot be accessed.  Close any application that is using this file and then try again.  You may need to restart your computer.

    We can't think of anything that has been changed, added or removed.  He doesn't do a lot of extra things with his computer, just runs a couple of the same applications every day.  It was upgraded from Office 2003 to Office 2007 one year ago but he just started having trouble now, and Oulook is something he uses all the time.

    If anyone has any ideas, it would be very helpful.  I saw online how I can run the truncation tool but I didn't know if this was something I should use here.  I saw other files to run but I didn't want to do anything until I understood more of what was going on here.  I would appreciate your help, thanks!

    Thursday, March 24, 2011 8:57 AM