How to change OST to PST  – Outlook?


It was very frustrating for me to see an error “xyz.ost is not an Outlook data file” again and again when I was trying to open an old OST file in Outlook 2016. Are you experiencing the similar things while accessing an offline .ost extension file in Outlook? Yes, of course, that’s why you are looking for an appropriate OST to PST conversion solution. Don’t worry here I am going to discuss the best way of converting Outlook OST to PST format so that you can save your precious data to be lost.

Basic scenarios where you may need to convert OST to PST?

All user who uses the Microsoft Outlook on a regular basis can better understand the need to convert OST to PST. There are some basic and major reasons to convert the OST to PST and these reasons are as follows-

  1. Distraction in the Outlook connection
  2. Sudden error in the Exchange Server or MS Outlook
  3. Virus issue in the hard disk
  4. Sudden or accidental deletion of the user account
  5. Transferring the email data and suddenly the OST file gets corrupted

For such difficulties, the following OST to PST conversion methods would help you immensely to bring back your OST file data from inaccessible to an accessible state.

Solution 1: Downloading Data again from the Exchange Server

This solution works for those users who are still connected with Exchange Server but unfortunately OST file has been deleted or altered from their profile. In that case, you can download data directly from the Exchange server again which is described here in detail. Follow the instructions to do the same:

  1. Start Outlook > Click Account Settings on the file tab >> Click Account settings
  2. Double-click your Microsoft Exchange account on the E-mail tab.
  3. Check the box “use cached Exchange mode” from offline setting and also drag the “Mail to keep offline slider” as per your requirement.Server Settings
  4. Click Next >> Ok then Finish.

Note: This method work in rare condition when you are properly connected with Exchange Server. If you want to convert archived, orphaned, corrupted or inaccessible OST file to PST format then you must go for a 2nd solution.

Solution 2: Converting an Archived or Inaccessible OST to PST with 3rd party solution

Before you begin the technique make sure that OST to PST converter is installed on your system which is required for modifying the .ost file extension to .pst format.

  1. Now launch the software you have downloaded and installed from the above link.
  2. Click on Add File button and browse your OST file which you want to convert to PST format.Select or Searct for OST file
  3. The software will scan and generate the preview of selected OST file data. Mail Daddy PST to OST
  4. Click on the Export button >> Select PST from Export option >> browse destination path then finally click on Export button to start the conversion. Export Emails
  5. It will take a few minutes to complete the OST conversion to PST. Wait till conversion ends and then open converted PST file with Outlook without any difficulty.

You may also like: 8 Tips And Tricks To Know More About Microsoft Outlook

Final Words: My name is Geeta Malik. I am very thankful to who allow me to write up this helpful post. I hope this article will help to may peoples for their several queries related to OST file, Exchange Server, and Outlook. If you are still facing any problem with OST to PST conversion then feel free to put a comment below.