It’s well-known that our Government Community Cloud instance of Office 365 doesn’t support emailing a channel. This can be problematic when you are attempting to schedule a channel meeting and include recipients not on the platform. What ends up happening is the recipient can actually receive an NDR (because they can’t send the meeting acceptance back to the channel).
To get around this, you can create a catch-all mailbox to capture the meeting responses using three quick PowerShell cmdlets from Exchange Online:
New-Mailbox -Shared -Alias 'catchall' -Name "Catch-All Mailbox" -DisplayName "Catch-All Mailbox" -Force New-DynamicDistributionGroup -Name 'AllMailboxes' -Alias 'AllMailboxes' -OrganizationalUnit $null -IncludedRecipients 'MailboxUsers' New-TransportRule -FromScope 'NotInOrganization' -RedirectMessageTo 'catchall' -ExceptIfSentToMemberOf AllMailboxes -Name 'AllMailboxes' -StopRuleProcessing:$false -Mode 'Enforce' -Comments 'Catch-all mailbox rule' -RuleErrorAction 'Ignore' -SenderAddressLocation 'Header'
That’s it. That’s the post. 🙂