1. Download MOS Migration tool from below url :
Microsoft Online Services Migration Tools (32 bit)
Microsoft Online Services Migration Tools (64 bit)
2. Log in to Administration Center for domain in BPOS-S and create a contact for the email address to whom you want to forward emails.
3. Launch the ‘Migration Command Shell’ from your programs folder.
4. Use the below cmdlet to set external forwarding.
Set-MSOnlineAlternateRecipient -Identity <email address of your hosted account> -AlternateRecipient <email address to forward to> -DeliverToBoth $true
*Note: The ‘$true’ on the end means it will leave a copy and forward. Change to ‘$false’ and it will only forward and not fill up mailbox.
*Note: If you want to remove a forwarder:
Clear-MSOnlineAlternateRecipient -Identity <email of hosted account>
Clear-MSOnlineAlternateRecipient -Identity [email protected]