.OST File in Use and Cannot Be Accessed


When I try to open the Outlook application on my PC, I receive an error message that reads:

The file C:\Users\NetID\AppData\Local\Microsoft\Outlook\NetID.ost is in use and cannot be accessed. Close any application that is using this file, and then try again. You might need to restart your computer.


  • Microsoft Windows
    • Outlook 2016


An error has occurred and the .OST file that Outlook needs to access your local email storage is unable to be opened. Generally a restart of your computer will reload any running programs and allow Outlook to access this file again. If this does not solve the problem, please contact the ITS Service Desk.


Article ID: 3284
Fri 4/26/19 1:54 PM
Fri 4/26/19 2:23 PM