Updated on 27 November 2014
Below are a few commands to covert user mailboxes to shared mailboxes in Office 365 (O365) Exchange Online.
If you have not already installed the required tools to connect to Office 365, please take the time to do so now before proceeding.
NOTE: The standard version of PowerShell that comes with the Windows OS will not be sufficient alone to run the O365 commands.
Connect to Office 365
Connect to Office 365 from an elevated PowerShell console…
Set-ExecutionPolicy -ExecutionPolicy RemoteSigned
$CRED = Get-Credential
$SESSION = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://ps.outlook.com/powershell -Credential $CRED -Authentication Basic -AllowRedirection
Connect-MsolService -Credential $CRED
Convert to Shared Mailbox
Convert mailbox and set size quota. NOTE: Shared and resource mailbox sizes increased from 5GB to 10GB in Q4 2013; and increased from 10GB to 50GB in Q4 2014.
Get-Mailbox -identity firstname.lastname@example.org | set-mailbox -type “Shared”
Set-Mailbox email@example.com -ProhibitSendReceiveQuota 50GB -ProhibitSendQuota 49.75GB -IssueWarningQuota 49.5GB
Assign permissions to specific group to access shared mailbox…
Add-MailboxPermission firstname.lastname@example.org -User "Engineering Group" -AccessRights FullAccess
Remove Office 365 License
Shared and Resource mailboxes do not require a license in Office 365. To remove an Office 365 license from shared mailbox to prevent from being charged for usage, perform the following commands…
$MSOLSKU = (Get-MSOLUser -UserPrincipalName email@example.com).Licenses.AccountSkuId
Set-MsolUserLicense -UserPrincipalName firstname.lastname@example.org -RemoveLicenses $MSOLSKU
Originally published on 14 Feb 2014 at http://oddytee.blogspot.com/2014/02/convert-user-mailboxes-to-shared.html