Learn How to Fix Outlook OST Error Message: ‘cannot open your default email folders, the file xxxx.ost is not an offline folder file’

admin | November 1st, 2016 | MS Exchange & Outlook

Make OST File Accessible

One of the most prominent feature of Outlook, which makes its usage wider is its offline mode synchronization. In case of server failure or breakdown, the users always find it convenient to work with offline OST file, which automatically gets synchronized to Exchange Server once the network is re-established. It can be said that this utility proves to be a boon for many users who cannot afford to delay their work due to server issues. However, problem arises when the user tries to connect to OST file and encounter an error that restricts access to the file. On such common error is” “Cannot open your default email folders, the file xxxx. ost is not an offline folder file.Due to this repeated situation, many users get into trouble and seek for a solution to overcome it. Here, we are going to discuss how to fix Outlook OST error message: ‘Cannot open your default email folders, the file xxxx.ost is not an offline folder file’.

Reason behind Outlook OST Error

The most probable reason behind such errors, which makes the OST file inaccessible is the corruption of OST file. The Offline folders are most prone to damage or virus attacks, which make them highly corrupted. Once corrupted, the OST file becomes unable to synchronize with the server. Moreover, the file becomes inaccessible in a way that even Outlook cannot recognize or sync with it. As a result, whenever an attempt is made to read or open OST file, Outlook throws an error indicating that it cannot open default emails folders or the file is not an offline folder file.

Some of the possible situations that makes the OST file corrupted include:

  • Faulty Disk sectors
  • Abnormal Outlook Termination
  • Network Related Issues
  • Sudden Power Loss

Tricks on how to fix Outlook OST Error Message : ‘Cannot open your default email folders, the file xxxx.ost is not an offline folder file’

Since the corrupted OST makes the situation terrible and impossible to work in an offline mode. An immediate step is required to repair damaged OST file so that it can again become useful to work with. The users can go for the following approaches to handle such OST files:

Approach 1: Run Scanost.exe

The foremost methodology is to repair the OST file by using an in-bulit Outlook utility, Scanost.exe. It is a way to diagnose and repair minor corrupted Outlook data files. So, one can choose to repair the corrupted file in the following manner:

  1. Browse the utility at Drive\Program Files\Microsoft Office.
  2. Click on Browse to select the corrupted OST file.
  3. Click on Start and monitor the file scanning process.
  4. The scan generates a list of encountered errors, click on Repair to handle those issues.

Once the utility completes its execution, re-start MS Outlook to view the OST file.

Limitation: The above discussed utility does not guarantee an efficient solution for major corrupted OST file. In many cases, it has been observed that the Outlook error still persists even after scanning and repairing the file with this utility.

Approach 2: Recreate OST

The users can also choose to recreate the offline folders and making certain changes in the cache mode of files. The inaccessible OST file can be recreated as:

  1. Firstly, close Outlook application.
  2. Open Control Panel & click on Mail >> Profiles.
  3. Choose the associated profile name.
  4. Select Properties >> Email Accounts.
  5. Choose the email address and click on Change.
  6. Under Advanced Settings, enable the option: Use Cached Exchange Mode.
  7. Click on OK to save changes.

Now, a new OST file will be created for the specified email account.

Automated Way to Fix Offline OST Error

If the error does not get resolved using the above stated techniques, the best approach is to go for an automated tool, Turgs OST Wizard. The software offers the following features to deal with all kinds of OST file issues:

  • Fix Outlook OST errors
  • Repair damaged or corrupted OST files
  • Recover OST data items: emails, contacts, calendars, task etc
  • Repair & extract corrupted OST into compatible formats such as PST, MSG, MBOX, PDF, EML, EMLX, MSG, HTML, MHTML, XPS, RTF, and DOC

Thus, users are advised to go for this utility to perform an error free and faster OST recovery.  The software instantaneously scans and repair the damaged OST file and makes it accessible for use.


Since, the most common reason behind every OST related error is corruption, it is always suggested to handle these files carefully. Understanding the significance of offline OST file, we have described the solution to overcome OST error. A compete methodology has been explained to let the users learn How to fix Outlook OST error message: ‘Cannot open your default email folders, the file xxxx.ost is not an offline folder file’. The manual as well as an automated, Turgs OST Wizard can be used to make the inaccessible OST file useful. Whether it is to convert OST to PST of Outlook or to convert Outlook OST to any selected format, the best suggested solution is to download OST Recovery tool from Turgs and get the job done.

Product page: https://turgs.com/ost/