Adding Send AS Mailbox Permissions to O365 Mailbox

If you are in the hybrid environment and looking for assigning mailbox permissions to migrated user on premises mailbox/s you will find below article handy. Changes are done on premises Active Directory needs to sync to Office 354 Azure Directory services via AD Sync.

Add-RecipientPermission (This cmdlet is available only in the cloud-based service.)

https://docs.microsoft.com/en-us/powershell/module/exchange/mailboxes/add-recipientpermission?view=exchange-ps

Add-MailboxPermission (This cmdlet is available in on-premises Exchange and in the cloud-based service)

https://docs.microsoft.com/en-us/powershell/module/exchange/mailboxes/add-mailboxpermission?view=exchange-ps

# VARS

$CloudMB1   = "Jason.Born@SecuredNinja.org"   # Cloud Mailbox

$SharedMB1  = "HRShared1@SecuredNinja.org"    # On prem

$SharedMB2  = "HRShared2@SecuredNinja.org"    # On prem

# ADDING  MB Permissions

Write-host "Adding AD Permissions"

Add-MailboxPermission –Identity $SharedMB1 –User $CloudMB1 `

                      –AccessRights FullAccess –AutoMapping $True -InheritanceType All -WhatIf

# VERIFY AD PERMISSIONS 

Write-host "Verifying AD Permissions"

$Output1 = Get-Mailbox -Identity $SharedMB1  | Get-MailboxPermission |`

where {$_.user.tostring() -ne "NT AUTHORITY\SELF" -and $_.IsInherited -eq $false} |`

Select-Object User,AccessRights,IsInherited,Deny

# ADD <SEND AS >

Write-host "Adding <SEND AS>  Permissions"

Add-RecipientPermission -Identity $SharedMB1 -Trustee $CloudMB1 -AccessRights SendAs -WhatIf

#VERIFY  <SEND AS>

Write-host "Verifying <SEND AS>  Permissions"

Get-RecipientPermission -Identity $SharedMB1

# REMOVE <SEND AS>

Write-host "REMOVING <SEND AS>  Permissions"

$removeUser = "Casey.Dedeal@SecuredNinja.org"

Remove-RecipientPermission -Identity $SharedMB2 -Trustee $removeUser -AccessRights SendAs -WhatIf

# REMOVE <FULL MB>

Write-host "REMOVING <FULL MB>  Permissions"

$CloudMB = "Casey.Dedeal@SecuredNinja.org"

Remove-MailboxPermission –Identity $SharedMB2 –User $CloudMB –AccessRights FullAccess -WhatIf

Casey DeDeal
Azure Certified Solutions Architect 
Principal Systems Engineer
https://msazure365.blogspot.com/ (blog)
https://simplepowershell.blogspot.com/  (blog)

https://twitter.com/Message_Talk (Twitter)