Definitely a problem on the receiving end
Error message 'Send As' and 'You do not have permission to send to this recipient'
A while ago I installed Exchange Server in a virtual machine to play around with it and see if I could get a good mail server up and running. I thought I did pretty well, as I was able to send and receive messages internally on the network and send emails to the internet.
However, when I logged in to a computer outside my network via Remote Desktop and tried to send an email to an account I had created on the Exchange Server, I got the following message:
Followed by some sort of message relay error:
