How to fix Outlook when your data file can't be accessed


This guide will help you fix the problem with Outlook not opening, or showing a 'data file (.pst) is already in use' error.


Is the file already in use?


First, check that the data file isn't being used by another program. You'll usually get an error message saying that the data file is already in use. This file has all the information about your email account in it, so Outlook will have a problem if it's already being used.

In most cases, restarting your computer will fix it, but sometimes there's another program that keeps trying to use the file. If you're still having problems after trying the next steps, you'll need to make a new Outlook profile.


Checking other programs


If the problem keeps coming back, then a program on your computer must be trying to use the Outlook data file. This could be:

  • Antivirus software that might be scanning all the files on your computer.
  • Cloud backup software that might be trying to backup the data file.
  • Cleaner tools that may be scanning or checking files.

Sometimes Windows will tell you what program is using the file. If it does, then closing that program will fix things. If the program is antivirus or backup software, you can change the settings of the program to ignore the Outlook data file, or change the scan or backup schedule to a time when you don't use Outlook.


Creating a new outlook profile


Open the Control panel.


Click the Mail icon.


Click on Show profiles.


Click Add, type a name for the new Profile, then press Add.


Type your Name, E-mail address, and Password in the boxes, and click Next.


Let Outlook set up the account, then click Finish.


You'll be back on the profile page, with the new one showing. Click Always use this profile at the bottom, and then choose the new profile in the drop down menu.


Click Apply, then click OK.

Close the Control Panel, and try opening Outlook again.


Hopefully, this is all the help you need. If the problem still isn’t fixed though, click here to get in touch with one of our Team Knowhow Experts.

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