A lot of questions come to us about how to export mailboxes to PST files within Office 365. In this article we will assume that there is to be no end-user interaction and you do not want to use any additional 3rd party tools
One of the first components is to add the correct Permissions to the account you will use to export the mailbox. Global Admin role is not enough to be able to complete this exercise, you need to have Compliance Administrator
Go to Azure Active Directory > Roles and Administrators and click on Compliance Administrators
Click on Assignments, Add Assignment and search for the user you want to add this permission to.
Next we need to go to https://protection.office.com and give some additional Permissions.
With the eDiscovery Manager blade open click on eDiscovery Administrator Edit
Then select the user are giving the eDiscovery Administrator permissions to
Now that we have set the correct Permissions, we need to go back to https://protection.office.com and create a Content Search
Click on New Search
We then leave the existing settings and click on Modify next to Specific Locations
On the next blade, we choose to specify users.
Once you have added the user you can click Done and Save
Click on Save & Run. You will need to give the search a name
When the search has completed you can see this in the list
If you then click on More you should be presented with the option to Export Result
In the section you need to ensure that you tick Enable De-duplication. This will ensure that you only get one export of each email that is the same. If there are multiple recipients of the same email address, you would have multiple exports. We also want all email messages in one file
The Export can take a while, depending on the size of the mailbox, so be patient.
When that has completed you can then click on the Export result and a new blade will open like this
Make sure you click on Copy to clipboard on the Export key
Click on Download Results to start the download. You will need to download and install the exporter tool, if not used before
When prompted you will need to Paste the export key that you previously copied
You will also specify where you want to save the downloaded file to
Once that has completed, you can then go and browse to the pst file that you just saved