Exporting PST Files from Exchange Online / Office 365
What is a PST File and what Prerequisites are Required?
Developed by Microsoft, a PST (Personal Storage Table) file allows users to store various types of data associated with Microsoft Outlook and other email clients. It can store copies of email messages, calendar events, contacts, and other items. With the sheer ubiquity of the Outlook client and how commonplace using PST files are these days, Microsoft has integrated native export functionality for Office 365’s Exchange Online Service user mailboxes to be exported into PST files, which can then be attached to Outlook email clients.
Occasionally, users may need to export the contents of a mailbox from Office 365 to be uploaded into DataCove. This can be the case when exporting large or selected user accounts from Office 365 that may take a longer time to import using the Exchange Crawler, or when creating an Application Registration for the Exchange Crawler is not possible.
Exporting a mailbox may be necessary for various reasons, including:
Exporting an existing mailbox that was retrieving mail via IMAP or POP3 after Microsoft turned off Basic Authentication for those methods.
Creating a backup copy of a past employee’s mailboxes for reference or compliance purposes.
Ensuring historical data is preserved with existing folder structure.
If planning to run multiple exports, it can be handy to get an understanding of just how much data will be exported in such a scenario. Running the Mailbox Size report will provide concrete numbers of exactly how much data is expected to come out before commencing exports.
Prerequisites
This guide is specifically for Exchange Online / Office 365 administrators and requires wide ranging permissions in the tenant to perform. Please be sure full Global Administrative access to the tenant is available before beginning or certain screens and dialog choices will not be available.
The recommended method to export a mailbox from Exchange Online is through the eDiscovery tool, which is included in most Office 365 licenses (E3/A3/G3 and above). If the existing license package does not support it, purchasing add-on licensing from Microsoft may be necessary to enable it.
When downloading the exported PST file, please use the Microsoft Edge browser. Using a different browser may yield errors on downloading, especially on larger files.
Assigning the eDiscovery Management Role and Permissions
To begin the export process, permission sets for eDiscovery Administrator or eDiscovery Manager, which are contained under the Discovery Management role, must be assigned to the user/administrator running the export.
Due to how Microsoft’s permission scheme is set up, certain functions are only visible if certain roles are assigned. For example, if a Global Administrator is running the export themselves, they also need these permissions assigned to themselves to receive the appropriate function additions.
To start with managing these permissions, head to the Microsoft 365 Admin Center and log in using a Global Administrator account.
On the left navigation pane of the Admin Center, click Exchange.
This will launch the Exchange Admin Center.
From the Exchange Admin Center’s left navigation pane, click Roles, then select Admin Roles.
From the list of admin roles that appear, select Discovery Management.
The Discovery Management role window will appear. Click the Assigned tab, then use the “+ Add” button to add the preferred user to this role.
After being added to the Discovery Management role, the assigned user will be able to perform searches of mailboxes in the Exchange organization.
After selecting the preferred users, click the blue Add button to add them as members to the role group.
Repeat these steps until all desired users have been added.
These now-authorized users will be able to perform the PST file export, which is covered in the next step.
Create an eDiscovery Case
Before specifying which email mailboxes to export, an eDiscovery Case must be created first. Microsoft’s eDiscovery module is designed to help organizations consolidate electronically stored information for legal cases, internal investigations, or compliance purposes.
Start by signing into the Microsoft Purview compliance portal.
From the left-hand navigation menu, select Solutions then eDiscovery.
From the eDiscovery page, select Standard Cases.
Use the + button to create a new case.
Name the new case, then click the blue Save button.
A new case has been created, which all upcoming search and export procedures will be filed under. The dialog box will close and take you back to the main eDiscovery Case management area.
With permissions assigned and a sorting area created, we can now move on to performing a search of the mailbox and exporting it to a PST file.
Search, Export and Download the PST File
From the list of eDiscovery cases, double-click on the Case created in the previous step.
Select Searches, then + New Search.
Create a name and description for the new search, then click the blue Next button.
On the Locations page, conduct the following steps:
Toggle Exchange Mailboxes to “On”
Deselect Add App Content for On-Premises Users
Select Choose users, groups, or teams.
From here, selection of the user mailboxes to be exported can be performed.
Search for the users within the search bar, then ensure they are checked.
After all users have been added, click the blue Done button.
Click the blue Next button to continue.
On the next screen, do not define any additional search conditions.
Click the blue Next button to continue to the next step.
Review the search information, then click the blue Submit button.
The search may take several seconds to complete. A success screen will appear confirming that the search has been created.
Click Done to complete the search.
From the list of searches, double click on the newly created search.
Click Actions, then Export results.
From the export results screen, select the following:
Output options: All items, including ones that have unrecognized format, are encrypted, or weren’t indexed for other reasons.
Export Exchange content as: One PST file containing all messages.
Then, click the blue Export button.
A dialog box will appear indicating that an export job has been created.
Click OK.
The search will now be visible under the Exports tab.
Depending on the size of the mailbox, it may take several hours for the export to be complete.
If the export is in progress, the following message will appear: “We’re getting your search results ready for download. This may take a while depending on the size of search results. You can also close this window and check back later”.
Once the export is complete, double click on the completed search. Then, click Download Results to download the exported PST file.
This will download the exported file to your local computer, after which an upload to DataCove or any other procedure can be performed.
Uploading the PST File to DataCove
With the PST file now exported from Exchange Online, it can be safely uploaded to the DataCove using the process described in this walkthrough article.