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). rebuild Outlook data file quickly 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)

An Outlook data files are designed to safely handle max space 50GB in Outlook 2010 to 2019 and Office 365 by default. 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. As it is converted, you can easily view the contents of the data file.

Outlook - OST file recurring corruption

You surely won't be disappointed with the results of rebuilding OST. As you change the extension, relaunch Outlook FixTechGuide Office 365 troubleshooting to rebuild your OST file. The first solid question that comes to mind is whether OST files are rebuildable. We are aware that OST files are directly connected to the Outlook email.

• Get your OST rebuilt properly with the help of the available techniques.
• Thus, you need to have a good anti-virus system to protect your computer.
• There may be items in the backup file that you might be able to recover that the Inbox Repair tool couldn't.
• Also, I forgot to mention that normally when the OST is corrupted you normally delete the file and recreate it.
• You could Right-click the Start button, and click Run, type Outlook.exe /safe, and click OK.
• Click the "Data Files" tab on the window and select your respective OST file.
• In addition, you could open outlook in safe mode, maybe some add-ins affect the outlook.
• Confirmed user can log on to OWA (Office 365 webmail) without issue.

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

In certain cases, you must go for other methods to recover the data across OST files. If the respective file is not rebuilding from the above methods, there are other ways to get its data. This can be done with the help of PST files, another Outlook data file form. While they act as the basic backup data file for the user, the OST file Outlook Not Sending or Receiving Email can be easily converted to this form. Also, I forgot to mention that normally when the OST is corrupted you normally delete the file and recreate it.