Method 2: Closing the PST / OST file from Outlook (Outlook 2013 and older only) If this method wasn’t applicable and all your email clients we’re already closed, move down to the next method below. If you see one, simply right-click on it and choose End Task. With this in mind, open up your Task Manager (Ctrl + Shift + Esc), go to the Processes tab and see if you see any evidence of an Outlook process that is currently running. Keep in mind that if Outlook.exe or a different application is running and is actively using the Data file, you’ll keep seeing the “ You Cannot Delete this Outlook Data File” error because the file is in use. Or it could be a different email client that is using the same Data file. If you receive this error message while trying to delete the Data file, you should start investigating if any instance of Outlook is currently running on your computer.

Not every potential fix will be applicable to your particular scenario, so we urge you to follow the methods in the order that they are presented and skip those that aren’t applicable.

Down below, you’ll find five different methods that affected users all over the world have successfully used to resolve the issue. If you’re currently struggling to resolve this particular error, this article will provide you with several troubleshooting steps. In this case, you might be successful by deleting the data file manually or by deleting the entire Outlook profile. If the PST / OST file contains bad data, you might be prevented from deleting it conventionally.

Corrupted Outlook profile – Another scenario that might trigger this particular issue is a corrupted Outlook profile.

Another approach is to close the PST / OST file from Outlook directly.

If this case is applicable, the fix is as simple as closing the email client (Outlook or other). The majority of users fail to delete the Outlook data file because Outlook is opened and is using it actively. Outlook (or a different email client) is using the data file – This is undoubtedly the most common scenario.

Outlook 365 delete emails at exit