OST File Recovery Tool for Windows 11/10: Easy Tutorial

About OST Files in Outlook

OST files (Offline Storage Table) are a critical component of Microsoft Outlook. They allow users to work with their emails, calendars, and contacts even when offline, with changes synced to the Exchange server once reconnected. When you add an Exchange or Microsoft 365 account to Outlook, Outlook will automatically generate an OST file locally. This file is encrypted and bound to both your email account and your computer.

By default, OST files are stored in a hidden folder:

C:\Users\[YourUserName]\AppData\Local\Microsoft\Outlook

Notes:✎...

If you can’t find this folder, open File Explorer, select the "View" tab, and check the "Hidden items" option—then you’ll be able to access the path.

However, much like other type of files, OST files can get lost, deleted, or corrupted due to system crashes, human error, or account removal and more. Will all those important personal and business emails, along with other data, be lost forever this way? Fortunately, there are several reliable methods and OST file recovery tools that can help you retrieve lost Microsoft 365 mailbox and data.

OST vs. PST

When it comes to OST files, PST files are an unavoidable topic. Both are Microsoft’s core data file formats that allow users to manage their email accounts conveniently and efficiently—but they function quite differently:

• OST files are cached copies of mailbox data from an Exchange, Outlook.com, or IMAP server, allowing offline access. It can sync local changes to the server effectively.
• PST files store emails, contacts, and other Outlook data locally, often used for archiving or POP3 accounts. It allows users to archive and manually store data locally.

Since PST files can be read directly by Outlook, converting a corrupted OST file to a PST file can help you extract data such as emails, contacts, and calendars in certain cases. And OST files are tied to specific Outlook profiles and accounts, which can make recovery more challenging.

How to Recover Lost OST File on Windows 10/11

If your OST file is lost or deleted due to accidental deletion, system crashes, hard drive formatting, or other such reasons, this section will provide several methods to help you retrieve the lost OST file—you can choose the most suitable one based on your needs. Let's explorer them one by one.

Regenerate the OST File

If you only accidentally deleted the OST file from the local folder, don't panic. OST files can usually be regenerated by re-syncing your email account.

Step 1. Locate to the OST file path in File Explorer, double-check for any remaining OST files. If there are any, manually delete them completely.

Step 2. Make sure to fully exit Outlook, then restart the Outlook app. Outlook will automatically start re-downloading all data from the server and generate a new, clean OST file.

Step 3. Once this process is complete, open the OST file path to check if the new OST file has been generated.

Restore Previous Versions

Restore Previous Versions is a Windows built-in feature that allows you to restore earlier versions of files and folders when you need. If you have enabled File History on Windows 10/11 and backed up the folder where the OST files were stored, you can use this tool to recover lost OST file.

Step 1. Navigate to the OST file folder and right click on it.

Step 2. Choose "Restore previous versions" from the context menu. Then a list of versions will be displayed.

Step 3. Select the version you want to restore and click "Restore".

OST File Recovery Tool Free Download—MyRecover

In worse-case scenarios, such as formatting C drive mistakenly or permanently deleting the entire folder where the OST file was stored, the two methods mentioned above may be far more challenging to work with. In such cases, MyRecover, a professional data recovery tool can help you retrieve lost OST file. It features an intuitive visual interface, allowing even novice users to complete data recovery with just a few clicks on the icons.

Step 1. Download and install MyRecover on your computer from Microsoft Store.

Step 2. Launch it and choose the C drive or the folder with lost OST file to scan, then click "Scan".

Step 3. Choose the OST files you would like to recover and click "Recover". You can use the "Filter" function to quickly access the files you wanted.

Step 4. Select a destination folder to save the recovered files.

Once the process is finished, the message "Files have been recovered successfully" will pop up. You can check them by clicking on the destination folder path or "Browse" button.

Convert OST to PST

While OST files allow you to access emails, contacts, and more even when offline, converting an OST file to a PST file is a better option in certain scenarios, such as when you need to back up data or extract data from a corrupted OST file. Several third-party tools, allow direct conversion. Once converted, the PST file can be imported into Outlook for full access to emails, contacts, and calendars.

The Bottom Line

Losing or corrupting your Outlook OST file can disrupt your workflow, but recovery is possible. From simple fixes like recreating the OST file or restoring previous versions to advanced methods like using MyRecover, you have multiple ways to restore your data. So, if you’re wondering how to recover missing PST file or OST file, MyRecover provides a trusted, professional solution.

For users with extensive recovery needs, the Professional Edition of MyRecover stands out. It offers unlimited data recovery and file content previewing features before restoration, making it a comprehensive OST file recovery tool for both individuals and businesses. Moreover, it allows recover data from laptop that won't boot.