Hello,
Let me explain my current setup: I want to send emails from mydomain.net with my mailcow instance, but I don’t want to receive any email on it. mydomain.net already receives emails on another server and I want to keep that one. So I set up subdomain.mydomain.net as a main domain and mydomain.net as an alias in Mailcow. It is working fine, I can send emails as anything@mydomain.net with no trouble… as long as the recipient is not something@mydomain.net.
Here is the error I get:
SMTP Error: The following recipients failed: something@mydomain.net: <something@mydomain.net>: Recipient address rejected: User unknown in virtual mailbox table
I totally understand this error. Mailcow tries to deliver the email locally, but it can’t as there is no mailbox corresponding to something@mydomain.net on this server. How can I configure it to use a specific SMTP server as a relay for recipients on domain mydomain.net?
I thought that Transport Maps could do it, so I tried to configure one in the Mailcow UI, but it didn’t change anything. I still get the exact same error. Here is what I configured:
