Create mail forwarding to an external email alias

User has an AD account in one domain with a particular email address. That address needs to be forward emails to another external email alias.

 

To resolve:

 

Create a mail user in Exchange 2010. Use the pshell one liner below to accomplish this

 

Enable-MailUser -Identity jdoe -Alias 'jdoe' -ExternalEmailAddress 'SMTP:alice@blahblah.org'