MS Outlook holds messages, appointments, notes, tasks, contacts, and other data items contained in the mailbox in PST files or OST files. Let us understand what differentiates these two file types of Outlook data files:

Outlook Data File (i.e. PST) is usually used for IMAP and POP3 email accounts.

Offline Outlook Data File (i.e. OST) comes into play when you chose to work offline with your Exchange account or decide to use Cached Mode of Exchange. Unlike PST, OST files can be easily created while Exchange Server is running.

For proper usage of Outlook email client, you need to configure one email account (for least). And each email account created with Outlook possesses a PST of its own. For instance, if you have created five email accounts, five individual PST files will be automatically created on your system. Also, these PST files will be attached to your Outlook profile.

But when PST files have been copied or moved from some external device or you have received them from other Outlook users, you can’t access your files unless they are added to your Outlook profile. This is how you can do this:

Such critical situations can only be resolved either by using a manual trick or by exploiting a specialized third-party tool.

Manual Way to add a PST file to Outlook

  1. Open Microsoft Outlook on your system, and click the File tab.
  2. In Open & Export, click the Import/Export tab.
  3. Click Import from another program or file, and then hit Next button in the Import & Export window that appears.
  4. Select Outlook Data File (.pst) and hit Next button.
  5. Browse for the PST file you wish to import. Under Options tab, select the action you want to proceed with i.e.
    • Replace duplicates with items imported
    • Allow duplicates to be created
    • Do not import duplicates
    • In the end, hit the Next button.
  6. Enter the password if your Outlook Data File is password-protected, and proceed by clicking OK.
  7. To import the contents of your PST file directly to Office 365 mailbox, select Import items into the same folder in: and specify the email account where you want to import files.If you don’t want to perform import function, simply choose Import items into the current folder and all your data will be imported to default folder.
  8. Click Finish. Once finished, the progress window will go away.

NOTE: If you are trying to import your PST file in Office 365 mailbox, a message saying ‘trying to connect with

Office 365’ will appear. This usually happens when interruptions in Internet Connection is encountered even for a second’s time. Outlook will continue with the import function once your Internet Connection will be established again.

Bonus Tip: If you want to retrieve some specific emails or contacts from your PST file, open the Outlook Data File, and then, simply drag and drop the emails and contacts from PST to existing Outlook files in the navigation pane.

But if your PST file is corrupt, you need to repair it before importing it to Outlook. For this, you can use a competent recovery tool like Outlook PST Repair. It can restore encrypted and password-protected files as well. The tool supports PST file recovery to another level and delivers instant results as well as integrates the preview function to view selected mailbox items by the user. The files can be filtered and split before export to the desired destination folder on the system. Check the complete features of the tool and related procedure via the free demo version by visiting the website.

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Outlook PST files obtained from external sources need to be imported or added to the Outlook profile to use them continuously. The blog delivered a manual way to perform the same and an outstanding utility to face the corrupt PST file and repair it efficiently.