Create Shared Mailbox For Internal Process


You want to create a shared mailbox for an internal business process.


New-Mailbox -Shared -Name "Internal Purchasing" -DisplayName "Internal Purchase Requests" -Alias InternalPurchasing |
Set-Mailbox -GrantSendOnBehalfTo PurchasingSG -RequireSenderAuthenticationEnabled $True |
Add-MailboxPermission -User PurchasingSG -AccessRights FullAccess -InheritanceType All


A common business need is a mailbox shared between several employees. This recipe creates a shared mailbox used for internal purchase requests. All of the members of PurchasingSG Distribution Group have FullAccess to the mailbox.

Internal Senders Only

Because all requests are for internal purchases, there is no need to deliver messages from external senders. Setting the -RequireSenderAuthenticationEnabled to $True means messages are accepted only from internal senders1. External senders will recieve an Undeliverable response with the error 550 5.7.134. This isn’t the only way to control message delivery to a mailbox. Transport rules2 can be crafted to do the same.

  1. See the -RequireSenderAuthenticationEnable documentation in the Set-Mailbox help 

  2. Documentation for New-TransportRule