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Shared mailboxes receive a maximum of 50Gb when no license is assigned
Microsoft has always said that a shared mailbox can be up to 50Gb unless you have assigned a license.
This is not the case in most tenants and this has always been tolerated by Microsoft.
Now they are really going to force this by capping shared mailboxes at 50Gb that do not have a license.
Here is the link for Exchange Online limits, including Shared mailbox capacities.
A PowerShell script to check if you have Shared Mailboxes above 50Gb
So, to make sure that your shared mailboxes in Exchange Online do not reach their limit, I have created a script that can check if you are close to the limit. the default is a 50Gb limit, but you can change this with a Parameter.
Exchange Online PowerShell module
I assume in the script that you are an administrator in Exchange Online, and that you already have the Exchange Online module installed.
The PowerShell module for EXO can be found here.
Using PowerShell for Exchange Online
The script needed to log in to Exchange Online.
Copy / paste it into PowerShell.
There are 2 optionable Parameters
The default is SharedMailbox. You can also use the script for other RecipientTypes.
The default is 50Gb. You can set the MaximumLimit with Gb only. The script will convert this to bytes.
You can set this to a lower amount to see which mailboxes are close to 50Gb.
When the property OverLimit equals True, the mailbox reached the limit.
Get-MailboxLimits Get-MailboxLimits -RecipientTypeDetails 'UserMailbox' Get-MailboxLimits -MaximumLimit 48 Get-MailboxLimits -RecipientTypeDetails 'UserMailbox' -MaximumLimit 45
If you have any questions about this script, you can leave a comment.