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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. 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. This is all most people will need, searching for older items will be slower but for daily use items it will still be quick. As you close them, lead to the folder and right-click on the OST file.

I can't repair corrupted Outlook .ost file

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If anyone can get an answer from microsoft on this issue I’d appreciate it. Any MS techs can contact me if they need further information or analysis. I’ve created a ticket today with Rackspace to see if their other customers are having this issue but I’m not hopeful on hearing back from them. 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.

Part 1: Can OST Files Be Rebuild?

Open the OST file as per the location provided in the table. As you open it across the File Explorer, lead to the “View” menu from the top. There, turn on the option of “File Name Extensions” to display extensions. Fwiw, responding to my original post and how we addressed it for this user - we ended up creating new Outlook profile and limiting the FixTechGuide support for Office 365 amount of cached mail to 2 years. This article has provided an overview of how you can quickly rebuild an OST file.

Method 3: Convert OST to PST

You might be working on something Exchange connectivity diagnostic 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. 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. This article offers to rebuild the OST file without putting you in any difficulty.

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

There may be items in the backup file that you might be able to recover that the solve Office 365 mailbox sync delays Inbox Repair tool couldn't. You can create a new Outlook Data File and drag the items in the Lost and Found folder into the new data file. After you've moved all the items, you can remove the Recovered Personal Folders (.pst) file, including the Lost and Found folder. To create a new Outlook Data File, go to Create an Outlook Data File. 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.

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There, turn on the option of “File Name Extensions” to display extensions.The Lost and Found folder contains any folders and items recovered by the repair tool that Outlook can't place in their original structure.If you can open the original Outlook Data File, you might be able to recover additional items.I’ve used the repair tool when this started and it did not really repair the file.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.We will help our readers decide the best way to rebuild OST for functioning through Outlook.You could Right-click the Start button, and click Run, type Outlook.exe /safe, and click OK.

Malware or virus attacks can cause great havoc across the computer. Virus attacks can directly attack the OST file, which would disrupt its data. Thus, you need to have a good anti-virus system to protect your computer. Find solutions to common problems or get help from a support agent.

Additional resources

Perfectly repair and recover corrupted Outlook PST & OST files. If the OST still gets corrupted when you have reduced the size there is something in the mailbox causing the problem. You must re-select “Account Settings” when it opens across a drop-down menu. There, lead into the “Data Files” tab and select your OST file. After selecting the file, click on “Open File Location” to redirect to the folder.