Microsoft always claims, that all data from a customer is only stored in that region, where the Office 365 contract is bound to. Now that means, that all SharePoint Online data and Exchange Online data will only be stored in the EMEA datacenters, when the contract is bound to Microsoft Austria for example.
Now if you take a look at http://o365datacentermap.azurewebsites.net/ there is already quite a big amount of datacenters existing (especially in the US and in EMEA). The point now is that, with the fast growth of Microsoft datacenters, customers do not know where their data is really stored, as it could make a difference for a company wether their mailboxes are stored in Austria or in Amsterdam or in Finland (due to legal restrictions).
So many IT admins ask the question: “How can I check where my mailbox data is actually stored?”
And I finally have come up with an answer to that question. In order to check where the O365 mailbox data is stored you can download and execute my PowerShell script from https://gallery.technet.microsoft.com/ExO-PowerShell-Get-storage-612c28fb and execute as follows to check all mailboxes in your O365 tenant:
.\exo_check_mailbox_location.ps1 -username firstname.lastname@example.org -password "Pa$$W0rd"
But sometimes you have the requirement that only some of your mailboxes need to be stored in a specific region due to legal restrictions. Therefore, you can use the same script with the following paramters:
.\exo_check_mailbox_location.ps1 -username email@example.com -password "Pa$$W0rd" -primarySMTPAddress firstname.lastname@example.org
After running this script you will get an output which is similar to the following:
So this script can be run on a scheduled base in order to check where your data is really stored, if you have some legal restrictions, which need to be taken into consideration when using Office 365…