Outlook Data File Corruption error

Question

Always getting Outlook Data File Corruption error. How to fix this and stop it to recur?

Answer 1

This error usually means the Outlook PST/OST data file is damaged. Common causes are Outlook being closed unexpectedly, disk errors, an oversized PST file, or storing the PST in OneDrive/network locations.

First, close Outlook completely.

If it is a PST file, run Microsoft’s Inbox Repair Tool (SCANPST.EXE), select the damaged PST and choose Repair. Instructions: https://support.microsoft.com/en-us/outlook/repair-outlook-data-files-pst-and-ost

If the error keeps coming back after repair, create a new Outlook profile: Control Panel > Mail > Show Profiles > Add, then add your email account again. This rebuilds the Outlook data file and is usually the best fix for recurring corruption.

Also make sure the PST is stored on the local drive, not OneDrive, NAS, or a network drive, as this can cause repeated corruption.

If it is an OST file, you normally do not need to repair it. Close Outlook, rename/delete the OST, then reopen Outlook and let it download a fresh copy from the mail server.

Answer 2

For recurring Outlook data file corruption, the fix depends on whether the damaged file is an .ost or .pst.

1. If the problem is with an .ost file
   • Close Outlook.
   • Open File Explorer and go to: %localappdata%\Microsoft\Outlook
   • Find the .ost file named in the error.
   • Delete it.
   • Start Outlook again.
   Outlook will recreate the offline cache and redownload mailbox data from the server. For Exchange accounts, deleting and rebuilding the .ost file is the recommended resolution for corruption.
2. If the problem is with a .pst file
   • Close Outlook.
   • Run the Inbox Repair Tool: SCANPST.EXE.
   • For Outlook 2016 or Outlook 2019, the tool is located in: C:\Program Files (x86)\Microsoft Office\root\Office16
   • In the tool, select Browse, choose the .pst file, select Start, and if errors are found, select Repair.
   • Back up the existing data file before repair. The tool also creates a backup during repair.
3. If Outlook still has problems after repair or rebuild
   • Create a new Outlook profile and start Outlook with that profile.
   • If Outlook opens normally with the new profile, the original profile is corrupted.
4. To help prevent recurrence
   • Install the latest Outlook updates. Outlook freezing and data file issues can occur when updates are missing.
   • If Outlook freezes or becomes unresponsive, run the Classic Outlook Advanced Diagnostics troubleshooter in Get Help. It can automatically check common causes such as add-ins, damaged data files, antivirus conflicts, and profile issues.
5. If the exact message is “Something is wrong with one of your data files and Outlook needs to close”
   • Update Outlook from File > Office Account > Update Options > Update Now.
   • That specific issue was fixed in Monthly Channel Version 2005 Build 12827.20470 and later.

Notes:

• SCANOST.EXE is no longer available starting in Outlook 2010.
• For Exchange accounts, rebuilding the .ost file is preferred over trying to repair it.
• Deleting an .ost file removes only the local offline cache; Outlook recreates it from the server.

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