Outlook PST File Migration

Author: Test

Migrate existing Outlook PST file content into users’ Microsoft 365 mailboxes. PST files are no longer supported for new email storage.

Purpose

The company is phasing out Outlook PST files to improve email reliability, accessibility, and data protection. Users are no longer permitted to move new emails into PST files. Outlook has been configured to prevent new emails from being transferred into PSTs.

Background

All email storage must now reside within the user’s Outlook mailbox where it is backed up and accessible through Microsoft 365. Existing PST files must be migrated into the user’s mailbox.

PST Migration Procedure

  1. Open Outlook.
  2. Verify that the user’s PST file is attached and accessible.
  3. Within the user’s Outlook mailbox (not the PST), create a new folder to organize the migrated emails if one does not already exist.
  4. Open the corresponding folder within the PST.
  5. Select the emails or folders to be migrated.
  6. Drag and drop the selected content into the newly created folder within the user’s Outlook mailbox.
  7. Allow Outlook sufficient time to upload and synchronize the emails with Microsoft 365. This may take several hours depending on mailbox size and network connection.
  8. Verify that the migrated emails appear in Outlook Web App (OWA) or another Outlook client to confirm successful synchronization.
  9. Keep Outlook open until synchronization has been completed.
  10. Once all required data has been migrated and verified, the PST file may be detached from Outlook if no longer needed.

Policy

New emails cannot be moved into PST files. All email must be stored within the user’s Outlook mailbox.

Benefits

Emails are securely stored within Microsoft 365 and included in the organization’s backup and retention policies. Users can access their email from Outlook Desktop, Outlook Web, and mobile devices. This eliminates risks associated with PST corruption or locally stored email files and simplifies mailbox management.