0x80040600OfficeCritical

Error 0x80040600 — Outlook Data File Corrupt | Microsoft Office Fix

Microsoft 365Office 2021Office 2019Office 2016

What Does 0x80040600 Mean?

The Outlook data file (PST or OST) is corrupted and cannot be read properly.

Real-World Causes

  1. 1Data file exceeded maximum size limit
  2. 2System crash or power failure while Outlook was writing to the file
  3. 3Disk errors or bad sectors corrupting the file
  4. 4Antivirus scanning/quarantining parts of the data file

Symptoms

  • Outlook crashes on startup
  • Missing emails, contacts, or calendar items
  • Error messages about data file integrity
  • Outlook freezes when accessing certain folders

DIY Fix

Beginner-friendly steps you can try at home

  1. 1Close Outlook completely before attempting repairs
  2. 2Run the Inbox Repair Tool: find scanpst.exe in the Office installation folder
  3. 3Run scanpst.exe, select the data file, and click Repair
  4. 4Repeat the repair process multiple times if needed

Advanced Fix

For experienced users and IT professionals

  1. 1Use the Outlook /resetnavpane switch to reset the navigation pane
  2. 2Import recovered items from the repair into a new PST file
  3. 3Use third-party PST repair tools for severe corruption
  4. 4If OST file: delete it and let Outlook rebuild from the server

Frequently Asked Questions

Where is scanpst.exe located?
Typical locations: C:\Program Files\Microsoft Office\root\Office16\ or C:\Program Files (x86)\Microsoft Office\root\Office16\. Search for 'scanpst.exe' in File Explorer if unsure.
Will I lose data if I repair the PST?
The Inbox Repair Tool creates a backup before repairing. Some severely corrupted items may not be recoverable. For Exchange/Microsoft 365 accounts, your emails are safe on the server — just delete the OST and resync.

Related Error Codes

About the Author

Windows Troubleshooting Team

Verified against official Microsoft documentation and real-world diagnostic data. Error behavior confirmed across Windows 10, Windows 11, and Windows Server.