Office 365: Mailboxes for testing your changes

You preparing for massive change on high number of mailboxes on your Office 365 tenant, but you want to test how the change will work first. But if there is no licences left, how it is possible to do?

Answer is quite straightforward – Shared mailboxes.

From mailbox properties perspective there are almost no difference between Regular and Shared mailboxes, but Shared mailboxes are free and it is possible to create unlimited number of Shared mailboxes on your Office 365 tenant.

Lets say you want to create 500 mailboxes for testing purposes. You will be surprised how simple it is! Just use following command in O365 PowerShell:

for ($i -eq 1; $i -ne 500; $i++) {New-Mailbox -Shared -Name “Test Shared Mailbox$i”}

 That particular command will create 500 new Shared mailboxes. You may want to play with red number ‘500’ to decrease or increase number of mailboxes you want to create.

Please note that Office 365 throttling policy will affect that operation. Probably number of mailboxes you will be able to create in one run is about 800. After that all administrative tasks will be denied for some time.

After testing is completed you can delete all mailboxes created by command above using following:

Get-mailbox | where {($_.Name -like ‘Test Shared Mailbox*’)} | Remove-Mailbox