The WebbyAcad OST Recovery Tool offers advanced features to fix damaged OST files and convert them to PST, EML, MSG and other formats while preserving folder hierarchy and metadata. It supports all Outlook versions and has no file size limitations, making it a comprehensive solution for recovering inaccessible OST data. I don’t have an answer to this other than to voice my suspicion that it is likely due to new Microsoft updates (windows and office). credential loop in Microsoft 365 Find the .ost file that the error message reported to have errors, and then delete it and open outlook, it will recreate a new .ost file. Change the Outlook sync settings to only keep a limited amount of mail off-line. If you only keep 6 or 12 months offline that will reduce the OST size significantly.

Repair Outlook Data Files (.pst and .ost)

If you're using an Exchange email account, you can delete the offline Outlook Data File (.ost) and Outlook will recreate the offline Outlook Data File (.ost) the next time you open Outlook. Even with the reg hack in place, I’ve found that ost files over 50gb tend to corrupt and become unusable with regularity. OST file corruption is a common problem faced by Outlook users like you. While you seek to counter this problem, you look for effective techniques. Although there are many methods to try, a few are productive.

Outlook - OST file recurring corruption

Although the repair process might recreate some of the folders, they may be empty. The Fix Outlook and Office 365 Errors 2025 Lost and Found folder contains any folders and items recovered by the repair tool that Outlook can't place in their original structure. You can use the Inbox Repair tool (SCANPST.EXE) to diagnose and repair errors in your Outlook data file.

• Open the OST file as per the location provided in the table.
• Convert your OST to PST for optimal results if rebuilding the OST file does not do the trick.
• The Inbox Repair tool checks the Outlook data files on your computer to see if they're in good shape.
• You can try syncing outlook file 6 to 12 months or through archiving email using retention policy, could be a better way to protect the .ost size from corrupt.
• The Inbox Repair tool creates a backup file with the same name as the original, but with a .bak extension, and saves it in the same folder.
• You can use the Inbox Repair tool (SCANPST.EXE) to diagnose and repair errors in your Outlook data file.

What are the major Reasons of OST Corruption and how to Fix it

When Outlook is running and is halted in such a way, it can damage the OST file. You might be working on something important across it when it happens. As you said Outlook E3 licenses should support at least 100GB of data & there’s no excuse why it can’t support OSTs above 50GB when they offer twice that space. In addition, you could open outlook in safe mode, maybe some add-ins affect the outlook. You could Right-click the Start button, and click Run, type Outlook.exe /safe, and click OK. Refer to this blog Solutions To Fix Error – "Errors Have Been Detected In The File Xxx.Ost" Solutions To Fix Error – "Errors Have Been Detected In The File Xxx.Ost" for the solution to this OST error.

Method 4: Use OST Repair Tool

This article has provided an overview of how you can quickly rebuild an OST file. With the methods and Wondershare Repairit for Email, you can make cohesive use of the available resources. Get your OST rebuilt properly with FixTechGuide email error solutions the help of the available techniques.