How to repair corrupted Outlook OST files?

OST files in Outlook 365 allow users to access their mailbox data even without an internet connection. But when these files become corrupted—due to system crashes, abrupt shutdowns, or synchronization failures—it can disrupt your workflow and make your mailbox contents inaccessible. This can be particularly problematic for professionals who depend on Outlook for day-to-day communication and scheduling.

To regain access to your data, repairing the corrupted OST file becomes essential. While Outlook has limited built-in options, they often fail when dealing with severely damaged or orphaned files. That’s where EdbMails OST to PST Converter proves effective. It enables you to recover data from damaged OST files and convert them into accessible PST format, preserving the original folder structure and formatting.

This guide walks you through the step-by-step process of repairing a corrupted OST file using both manual methods and EdbMails, helping you restore full access to your Outlook 365 mailbox.

1. How to repair and fix a corrupted OST file?

   To repair a corrupted OST file, you can use a built-in utility like ScanPST.exe or a third-party software like EdbMails OST to PST converter. If the corruption is severe, or if built-in utilities are unable to repair the OST file, EdbMails can help recover and repair the OST file completely to make it usable again.

   The following are some of the methods to repair Outlook data files from corruption.

   • Method 1: Use the Inbox Repair tool (ScanPST.exe)

     Microsoft Outlook comes with a built-in Inbox Repair tool that can help repair corrupted PST and OST files. Here are the steps to use the Inbox Repair tool to repair a corrupted OST file:

     • Step 1: Close Outlook and related processes

       Ensure that Microsoft Outlook is closed and that there are no Outlook processes running in the background.

     • Step 2: Find the ScanPST.exe tool in your computer
       • The ScanPST.exe tool is a built-in repair utility in Microsoft Outlook.
       • The location of ScanPST.exe may vary depending on the version of Outlook you're using. However, it can usually be found in the Office installation folder.
       • The default location for this file is

         C:\Program Files\Microsoft Office\OfficeXX\ScanPST.exe

       Note: Replace ‘XX’ with the version of Office installed on your computer (e.g., Office16 for Office 2016)

     • Step 3: Run the ScanPST.exe tool for OST repair
       • Double-click on ScanPST.exe to open it.
       • Click ‘Browse’ and select the OST file that you want to repair.
       • Click ‘Start’ to begin the scan process.
       • The ScanPST.exe tool will analyze the OST file and attempt to repair any errors it finds.
       • The tool scans the OST file and displays a summary of the scan results.
       • Click the ‘Repair’ to repair the issues.
       • After the repair process is complete, you can re-open Microsoft Outlook and check whether you are able to access your mailbox data.

         

       Note: The Inbox Repair tool can only fix minor issues with the OST file. If your OST file is severely corrupted or if the Outlook emails are not syncing, this method may not be suitable to repair the Outlook data file. In that case, you may need to use EdbMails to fix OST corruption.

   • Method 2: Create a new OST file by reconfiguring the Outlook profile

     If the previous method did not work, you can try creating a new OST file. Here are the steps to create a new OST file:

     • Step 1: Exit Microsoft Outlook and close related processes
       • Go to ‘File’ > and click ‘Exit’
       • Ensure that Microsoft Outlook is closed and that there are no Outlook processes running in the background.
     • Step 2: Rename the Corrupted OST file
       • Find the location of the corrupted OST file by going to ‘File’ > ’Account Settings’ > ‘Account Settings’ > ’Data Files’ > ‘Open File Location’

         

       • Right-click on the file and select ‘Rename’.
       • Rename the file by adding .old to the end of the file name (e.g., MyFile.ost.old).
     • Step 3: Create a New Outlook Profile
       • Click on the Windows Start menu and search for ‘Control Panel’.
       • Click on the ‘Mail’ applet to open the Mail Setup dialog box.
       • Click the ‘Show Profiles’ button and then click the ‘Add’ button to create a new Outlook profile.

         

       • Enter a name for the new profile and follow the prompts to set up your email account in the new profile.
     • Step 4: Start Outlook with the new profile
       • Once the new profile has been created, click on ‘OK’ to close the Mail Setup dialog box.
       • Open Microsoft Outlook and select the new profile you just created.
       • Outlook will begin creating a new OST file to replace the old one.
     • Step 5: Synchronize your mailbox with the server
       • After a new OST file has been created, Outlook starts synchronizing your mailbox with the Exchange Server.
       • Depending on the size of your mailbox, this process may take some time to complete.
       • After the synchronization process is complete, you can begin using Outlook as normal.

       Note: This method may result in the loss of some data that was not synchronized with the Exchange Server before the OST corruption occurred. It is therefore recommended to back up your mailbox data by converting the OST to PST file.

   • Method 3: Use EdbMails tool for Outlook OST repair

     ScanPST can only repair minor OST file errors and cannot repair severe OST file corruption. In such cases, you can use a third-party tool such as EdbMails OST to PST converter, to repair and convert the OST to PST. It is the best method for recovering deleted mailbox items, password-protected OST files, and large OST files without using ScanPST.

     Here’s how you can repair a corrupted OST file with EdbMails

     • Step 1: Install EdbMails OST repair and converter tool

       • To get started, download and install the latest version of EdbMails application on your computer.

         

       • Log in with your email address and password, or click ‘Start Your Free Trial’ to access the features without creating an account.

         

       • Select ‘Outlook OST Recovery and Migration’.

         

       • Choose ‘OST to PST’ from the option.

         

       • You can proceed with the default job name or click ‘New Job’ to assign a custom job name.

         

     • Step 2: Browse the corrupt OST file to repair

       • Click ‘Browse for OST file'.

         

       • Choose the OST file from your computer and click ‘Next’ to continue. If the file is stored on a network drive, make sure it has both read and write permissions to ensure it opens without issues.

         

       • Click ‘Browse’.

         

       • Select the location to save the exported PST files. Ensure you have enough free disk space for storage.

         

     • Step 3: Preview and select the mailbox

       • EdbMails automatically scans the OST file and displays the contents

         

       • After the repair is finished, you’ll see the full folder structure on the left side. Simply expand the mailbox and its folders to preview the contents. The preview pane lets you view emails, contacts, notes, tasks, calendars, and more—right within the application.
       • Select the required mailboxes/folders and click the ‘Next’ button.

         

     • Step 4: Export Outlook OST files

       • Verify the mailboxes and folders selected for export operation.
       • Make sure the ‘Action’ is set to 'Export', then click the 'Start Export' button.

         

       • The export operation is now initiated, and you can monitor it in the progress bar. Wait for the operation to complete and verify the exported items with the log report.

         

     • Step 5: Import and add the PST file in Outlook

       Finally, import the PST file into Outlook. After the import is complete, you will have access to all of the data that was exported from the OST file in the PST file format.

       • Open Outlook > go to ‘File’
       • In the 'Info' section, click on ‘Open & Export’
       • select ‘Import/Export’
       • In the ‘Import and Export Wizard’, select ‘Import from another program or file’ and click ‘Next’.
       • Select ‘Outlook Data File (.pst)’ and follow the steps to start importing the file into Outlook.

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Additional resources

• Your mailbox has been temporarily moved on Exchange server
• Open OST file in Outlook
• Save Outlook emails to hard drive
• Import OST file into Outlook
• Your Outlook data file cannot be configured