Need to delete .ost file


  • I cannot open a live connection to my Outlook 2007 email in Windows 7. I receive the following message: "Cannot open your default email folders. Outlook is using an old copy of your Online Folder (.ost). Exit Outlook, delete the .ost file, and restart Outlook. A new file will be automatically created the next time you initiate a send/receive"ginhe11

    Could someone please provide me with step by step directions on how to accomplish this? Should the Cached Exchange Mode be on or off (Tools, Account Settings, Email Tab, double click on Microsoft Exchange).

    Thank you,

    Saturday, March 13, 2010 7:22 PM


All replies

  • with outlook closed: delete the outlook.ost file from c:\users\username\appdata\Roaming\Microsoft\Outlook\

    restart outlook and it will work.
    • Proposed as answer by DrX69 Monday, March 15, 2010 3:56 AM
    • Marked as answer by Sean Zhu -Moderator Monday, March 22, 2010 3:50 AM
    Monday, March 15, 2010 3:56 AM
  • You can also try this:

    1.       Open Outlook, Tools->Account settings->More settings->Advanced tab->Offline folder File Settings.
    2.       Press the button "Disable offline use".
    3.       Press OK and exit Outlook.

    For Outlook 2007 related issue, you can also post it in the following discussion group:

    Hope this helps!
    Sean Zhu - MSFT
    Monday, March 15, 2010 6:30 AM
  • Dear All,

    I faced a problem same as all of you, but i found out the we have to do "Change Folder" from the Exchange server to local PST file.....


    Friday, November 04, 2011 4:54 AM
  • This is a stupid answer and not very well thought out.  Personally, I don't have broadband access at home and my only access to my exchange account is via AT&T mobile.  Therefore, with a 5GB mailbox and at $10/GB, this is $50 proposition every time it happens.  My current *.ost file has all the data I need, so why would I want to delete a file and recreate it for $50 when all the data is already there..... dumb... just dumb! 
    Saturday, May 26, 2012 9:47 PM
  • Randy, what good is "all the data" if you can't access it?   Fortunately, there are free utilities one can use to fix a corrupt .PST or .OST file.  One such comes with Outlook and is called "scanpst.exe".  You'll have to search c:\program files\microsoft office\office12 (or 14) for it.  Note, the utilities don't always fix whatever the problem may be, but if they do, you're golden. 
    • Proposed as answer by AlunJ Tuesday, August 28, 2012 12:55 PM
    Thursday, July 05, 2012 5:32 PM
  • Sean,

    Though your answer is 3.5 years old, your instructions were easy to follow, and most importantly, my .ost files are GONE!!!!  Maybe my headache will be gone soon also.

    Kudos!!!  Thank you!!!

    Monday, October 07, 2013 4:06 PM
  • with outlook closed: delete the outlook.ost file from c:\users\username\appdata\Roaming\Microsoft\Outlook\

    restart outlook and it will work.

    Microsoft Outlook 2010 has my .ost files in c:\users\username\appdata\Local\Microsoft\Outlook\

    Thursday, October 31, 2013 12:19 AM
  • who doesn't have broadband access
    Tuesday, July 08, 2014 2:57 PM
  • JibsMan

    Thank You!

    I spent 30 min trying to figure out why it would not work because the other guys forgot the "Local" in the syntax.


    Friday, August 08, 2014 9:25 PM
  • It'd be immensely helpful if Outlook would just give users an option to delete the thing and restart Outlook right from the dialog, rather than requiring users to troll the internet looking for a hint on where this file is located. Better still, just fix it silently and move on.
    Wednesday, February 11, 2015 5:54 AM
  • This worked for me!  I found the .ost file in the LOCAL folder, not the ROAMING. 

    THANK YOU!!!

    Thursday, June 25, 2015 2:37 PM
  • LOCAL not ROAMING. see below thread posts. I had the same problem.
    Tuesday, October 18, 2016 12:18 PM