You've just tried to open Outlook and got hit with error 0x80040600. Your emails are locked behind this cryptic code, and nothing you've tried online has worked. I see this exact problem almost weekly on remote support calls, and the good news is: it's fixable in most cases. The bad news: you need to act quickly and choose the right method, because the wrong approach can permanently delete your data.

TL;DR

Outlook error 0x80040600 means your PST file is corrupted. Try Microsoft's ScanPST.exe repair tool first (60-70% success rate), but expect it may delete corrupted items. If that fails, create a new Outlook profile and import your PST data. For severe corruption, use third-party recovery tools like Stellar Repair (85-95% success rate). Always backup before attempting any repair.

⏱️ 14 min read✅ 70-85% success rate📅 Updated May 2026

Key Takeaways

Error 0x80040600 indicates PST file corruption from crashes, oversized files, or cloud storage conflicts
ScanPST.exe is free but may permanently delete corrupted data; always backup first
Creating a new Outlook profile bypasses corrupted profile settings without losing data
Third-party recovery tools recover 85-95% of data from severely damaged PST files
Prevention through regular backups, proper shutdowns, and file size limits saves hours of troubleshooting

At a Glance

Difficulty: Medium
Time Required: 30-60 minutes
Success Rate: 70-85% depending on corruption severity

What Causes Outlook Error 0x80040600?

This error appears when Outlook tries to read your PST file and discovers the file structure is damaged or unreadable. Think of a PST like a filing cabinet: if the drawers are locked, the labels are torn off, or the contents are scrambled, you can't access anything inside. That's what 0x80040600 means to your Outlook installation.

The most common culprit is unexpected shutdowns. If Windows crashes or loses power while Outlook is writing data to the PST, the file gets left in an inconsistent state. The header becomes corrupted, tables go missing, and Outlook refuses to open it. I've traced at least three calls this month to PST files stored in OneDrive or Dropbox. Cloud syncing causes file locking conflicts that corrupt the PST structure mid-write. Another frequent cause: oversized PST files. If your PST exceeds 50GB (older Outlook versions) or creeps toward 100GB (newer versions), the file becomes unstable and prone to crashes during read operations.

Antivirus software can also trigger this. Real-time scanning locks the PST while it's being accessed, or worse, antivirus aggressive scan modes actually corrupt the file if they're configured poorly. And then there's malware, genuine infections can encrypt or deliberately corrupt your PST. Hardware failures are less common but catastrophic: if your drive develops bad sectors where the PST sits, specific file blocks become unreadable.

Quick Fix: Use Microsoft's ScanPST Repair Tool

Repair with ScanPST.exe Medium

Close Outlook completely. Check Task Manager (Ctrl+Shift+Esc) and ensure no OUTLOOK.EXE processes remain running. Close any Outlook windows, then wait 10 seconds before proceeding.
Locate ScanPST.exe for your Outlook version. Use Windows+R and type cmd. Navigate to the Outlook installation folder: For Outlook 2016/2019/2021/365, type cd "C:\Program Files\Microsoft Office\root\Office16". For Outlook 2013, use cd "C:\Program Files\Microsoft Office\Office15". Type SCANPST.EXE to launch.
Manually backup your PST file first. Open File Explorer, navigate to C:\Users\[YourUsername]\AppData\Local\Microsoft\Outlook or check File > Account Settings > Data Files to locate your PST. Copy the PST file to an external drive or a different folder. This is non-negotiable, ScanPST may delete corrupted items permanently.
Run the scan. In ScanPST, click Browse and select your PST file. Click Start. The scan will take 15-60 minutes depending on file size. Do not interrupt the process.
Review results and repair. Once scanning completes, check the errors found. Ensure 'Make backup of scanned file before repairing' is ticked (creates a .bak file). Click Repair.
Verify Outlook opens. Close ScanPST and launch Outlook. Check if error 0x80040600 is gone. Verify folders load and emails are visible. Check the Recovered Personal Folders for any salvaged items.

If Outlook opens and your data is intact, you're done. ScanPST has fixed the corruption. Move your PST back to its original location if you haven't already.

Important: ScanPST may permanently delete corrupted folders and messages to repair the file. Success rate is only 60-70% for mild to moderate corruption. For severe cases or very large PST files (over 5GB), the tool often crashes or fails to complete. If this happens, skip to the third-party recovery tool solution below.

More Advanced Fix: Create a New Outlook Profile

New Profile Method Medium

Open Control Panel mail settings. Click Start, type mail, and select 'Mail (Microsoft Outlook)'. Click 'Show Profiles'.
Create a new profile. Click Add, enter a new profile name like 'Outlook Clean', and click OK. When prompted to set up an email account, you can either configure your account now or skip this step.
Set the new profile as default. Back in the Mail Setup window, select your new profile. Choose 'Always use this profile' if you want to use it going forward, or 'Prompt for a profile to be used' if you want to switch between profiles. Click OK.
Launch Outlook with the new profile. Close the Control Panel window. Open Outlook. If prompted, select your new profile from the dropdown. Outlook should launch without the 0x80040600 error because this profile has clean settings and no corrupted data files yet.
Add your original PST to the new profile. Once Outlook opens, go to File > Account Settings > Account Settings > Data Files tab. Click Add. Browse to your original PST file location and select it. Click OK. Your PST will now appear in the left folder pane under the new profile.
Import data if the PST won't open directly. If the PST still refuses to open in the new profile, go to File > Open & Export > Import/Export. Select 'Import from another programme or file' and choose 'Outlook Data File (.pst)'. Select your PST file and follow the import wizard. This imports all recoverable data into the new profile's default PST.

Your new profile is now functional and your data is accessible through either the attached PST or the imported data. Reconfigure your email account, signatures, and preferences as needed.

This method works well when the corruption is profile-related rather than file-related. A fresh profile has clean configuration files, so Outlook can often read the PST without the 0x80040600 error. This approach is gentler than ScanPST and avoids permanent data deletion.

Advanced Fix: Third-Party PST Recovery Tools

If both ScanPST and the new profile method fail, or if you need to recover maximum data from a severely corrupted PST, third-party recovery tools are your best option. These programs perform deep scanning of the corrupted PST structure and extract recoverable emails, contacts, calendars, and attachments even when Outlook can't read the file at all. Success rates sit at 85-95% for severe corruption cases.

Professional PST Recovery Advanced

Copy your PST to a safe location. Create a working copy of your corrupted PST on an external drive or separate folder. Never run recovery tools on the original file. Verify the copy is complete and matches the original file size.
Download a reputable recovery tool. Research and select from established vendors: Stellar Repair for Outlook, Kernel for Outlook PST Repair, or RecoveryFix. Download only from official vendor websites to avoid malware-infected counterfeit tools. Most offer free trials that allow preview of recoverable data without paying.
Install the tool and launch a deep scan. Follow the vendor's installation instructions. Open the recovery tool, click Browse or Select File, and navigate to your PST copy. Choose 'Deep Scan' or 'Advanced Scan' mode (not quick scan). Start the scanning process. Large files (over 10GB) may take 1-2 hours to scan completely. Do not interrupt.
Preview recoverable data. Once the scan completes, the tool displays a folder tree showing all recoverable emails, contacts, calendar items, and attachments. Navigate through folders and preview individual items to verify critical data is recoverable. Check file counts and date ranges to ensure completeness.
Purchase a licence and export recovered data. If the preview confirms your data is recoverable, purchase the full licence from the vendor (typically £40-£150 depending on tool and features). Unlock the save functionality. Select 'Export as PST' or 'Save as Outlook Data File'. Choose a destination folder with adequate free space (at least 2x the original PST size). The tool creates a new, repaired PST file with all recovered data.
Import the recovered PST into Outlook. Open Outlook. Go to File > Open & Export > Open Outlook Data File and select the new recovered PST. Or use File > Account Settings > Data Files > Add to attach the recovered PST to your profile. Verify all folders, emails, and data are now accessible without errors.

Your data is recovered and accessible in Outlook. The new PST file created by the recovery tool is stable and ready for long-term use. Archive or delete the original corrupted PST once you've confirmed all critical data is present in the recovered version.

Cost and Limitations: Most recovery tools require payment for full functionality. Free trials typically allow preview only. Download times and scanning times increase dramatically with file size (50GB PST may take 2-3 hours to scan). Some severely corrupted files may only recover 70-80% of data even with professional tools. Always check vendor reviews on independent sites before purchasing.

I've used Stellar Repair on particularly stubborn cases at Vivid Repairs, and it consistently recovers data that ScanPST leaves behind. The deep scan algorithm rebuilds the file structure from raw data blocks, which is why it works on files so corrupted that Outlook completely refuses them. The trade-off is cost and time, but if your PST contains irreplaceable business emails or historical data, it's worth the investment.

When Hardware Is the Real Problem

Before you assume the PST is just corrupt, consider whether your hard drive itself might be failing. If you're seeing 0x80040600 repeatedly even after repairs, or if other files on the drive are becoming inaccessible, bad sectors are likely the culprit. You can check this by opening Command Prompt as Administrator and running chkdsk C: /F /R (replace C with your drive letter). This scans the drive for bad sectors. If errors are found, the drive is failing and should be replaced soon. Data recovery from a failing drive requires professional services and costs significantly more than repairing a PST file.

If you discover drive issues, stop using that drive for critical work immediately and back up everything to external storage or cloud. A failing drive can corrupt multiple files, not just your PST.

Preventing Outlook Error 0x80040600 Forever

Prevention is infinitely cheaper than recovery. Once you've fixed this error, implement these practices to avoid repeating the nightmare.

Backup religiously. Set up automatic weekly backups of your Outlook PST folder to external storage or a non-synced cloud service. Windows Backup, Macrium Reflect, or even simple scheduled xcopy commands work fine. If corruption happens again, you can restore from a recent clean backup instead of fighting with repair tools.

Keep PST files small. Split large PST files into multiple files by year or by category. Keep your active PST under 20GB. Larger files are unstable and more prone to corruption. Archive old emails to a separate PST for cold storage. Most users never need to search back more than 2-3 years anyway.

Never store PST files in cloud-synced folders. This is the single biggest mistake I see. OneDrive, Dropbox, and Google Drive create file-locking conflicts that corrupt PST structures. Store your PST on your local C: drive only, preferably not on the same partition as your operating system if possible. If your work requires cloud synchronisation, use Exchange or Office 365, not local PST files.

Exit Outlook properly. Use File > Exit or close all Outlook windows and wait for the process to fully terminate. Don't force-close Outlook, don't shut down Windows with Outlook running, and don't pull the power cable. Abrupt exits are one of the top causes of PST corruption.

Exclude your PST from antivirus real-time scanning. Configure your antivirus (Windows Defender, Avast, Norton, etc.) to skip the Outlook PST folder during real-time scans. Schedule full scans for evenings when Outlook is closed. Real-time antivirus interference is surprisingly common and easily preventable.

Use 64-bit Outlook if your system supports it. 64-bit Outlook handles large files more gracefully and has better memory management. It won't fix existing corruption, but it reduces future corruption risk, especially for files over 4GB. Check your Windows version: if it's Windows 10/11 64-bit, install Office 365 or Office 2021 in 64-bit mode.

Install a UPS (Uninterruptible Power Supply). A modest £100-150 UPS protects your PC from power surges and unexpected shutdowns. Many PST corruptions trace directly to power failures during file writes. A UPS gives your PC time to gracefully shut down if power is lost.

Monitor file sizes regularly. Check your PST size monthly via File > Account Settings > Data Files > Settings. If it's approaching 50GB (32-bit Outlook limit) or 100GB (64-bit limit), start archiving immediately. Don't wait until the file becomes unstable.

Outlook Error 0x80040600 Summary

Outlook error 0x80040600 is frustrating, but it's almost always fixable if you act quickly and choose the right method. Start with ScanPST.exe if your PST is under 5GB and corruption is mild. If that fails or your file is very large, create a new Outlook profile and import your data, this bypasses corrupted settings without permanent data loss. For severe corruption that defeats both methods, invest in a third-party recovery tool like Stellar Repair, which recovers 85-95% of data by performing deep file scanning.

Once your Outlook is working again, implement regular backups, keep PST files under 20GB, store them on local drives only (never OneDrive), and always exit Outlook properly before shutdowns. These habits prevent 90% of PST corruption cases. If you get stuck or the error persists after attempting these fixes, remote support can diagnose whether the problem is profile corruption, hardware failure, or data file damage that requires professional recovery services.

Outlook error 0x80040600 PST file corrupt cannot open