Ways to Repair and View Corrupted OST File

An Offline Storage Table or OST file may get corrupt or damaged for various reasons, such as abrupt shutdown, power failure, system crash, incompatible or faulty add-ins, etc. OST files may also become inaccessible due to oversizing or when the user profile is either removed or disabled from the mail server. 

A corrupt OST prevents users from accessing their Outlook mail items, such as emails, contacts, attachments, tasks, calendar items, etc. and may lead to the following errors,

Cannot start Microsoft Outlook…….The file C:\....\abc.ost is not an Outlook data file (.ost)

The file C:\Users\xxx\xxx.ost cannot be opened

Error have been detected in the file C:\Users\....\xxx.ost

Microsoft Outlook exited without properly closing your Outlook data file C:\...\abc@xyz.com.ost. Microsoft Outlook must be restarted.

If you are experiencing any of these or similar errors related to the Outlook data files (.ost), you must fix it by repairing the damaged OST file to view it.

Below we have discussed some ways to repair and view corrupted or inaccessible OST files with the help of built-in utilities and third-party tools.

Ways to Repair and View Corrupt OST File

Fundamentally, the OST file is much more robust and reliable than other Outlook data files, such as PST—which is more susceptible to damage. However, in most cases, the OST file becomes inaccessible due to inconsistencies with the OST file.

Below we have discussed a few methods that you may follow to repair and view corrupt OST files.

1. Update Folder Manually

If you can access Outlook but experiencing issues with the OST synchronization or find a particular folder with missing or outdated mail items, you can manually update that folder in Outlook.

The steps are as follow,

• Open Outlook
• Right-click on the folder with missing or outdated mail items and choose Properties.
• Click Clear Offline Items and then click OK.

• Finally, click the Send/Receive tab and click on the Update Folder option.

If your profile is active and the OST file isn't damaged, it will synchronize the mail item. However, if you see an error while updating the folder, follow the next methods to repair and view the corrupted OST file.

2. Use Inbox Repair Tool

Inbox Repair Tool or SCANPST.exe is Microsoft's Outlook data file repair utility to repair damaged or corrupt OST and PST files.

In some cases, the Inbox Repair Tool may automatically open and prompt you to repair the corrupt OST file. However, you can also manually scan and repair a corrupt or inaccessible OST file by using this utility, which is located in the MS Office (Outlook) installation directory.

The exact location of SCANPST.exe varies based on the version of Windows and Outlook you are using. Once you have found the SCANPST.exe, launch the utility and follow these steps,

• Click the Browse button and choose the corrupt OST file.
• After choosing the corrupt OST file, click the Start button to scan the damaged OST file.
• After the scan, verify that the backup option is selected. Then click the Repair button to start repairing the OST file.

• After the repair is done, you will see a prompt, click OK.

• You may now open Outlook to check if you can access it and all your mail items.

However, if SCANPST fails to repair the corrupt OST file, you need to recreate the OST file to fix the problem. Follow the next method to learn more.

3. Recreate OST File

If the SCANPST or Inbox Repair Tool fails to repair the corrupt OST file, you can recreate a new OST file to fix the problem. The steps are as follow,

• Close Outlook, if open.
• Locate the default OST file. You can right-click on your profile name in Outlook and choose Open File Location to locate the OST file. You may also follow the link mentioned in Method 2 to locate the OST file.
• Once located, copy and backup the OST file to another safe location and then delete the OST file from the default location.

• After deleting the OST file, launch Outlook. This will create a new OST file and fix the corruption and synchronization issues.

To Wrap Up

Hopefully, the fixes discussed in the post will help you repair and view the corrupt OST file. However, these methods may not work if the OST is severely corrupt or your profile is disabled or deleted from the Exchange or Office 365 mailbox server. In such a case, OST file recreation will fail. But you can always use an OST to PST Converter tool, to convert your inaccessible or damaged OST file to Outlook importable PST and then view it in any Outlook client on Windows or Mac.

It's the most reliable and secure way to restore and view your mail items from a corrupt or inaccessible OST file.