Cannot send to btinternet addresses from Exchange 2010
I have a Windows SBS 2011 with Exchange 2010. It's a new server and doesn't replace any previous Windows servers.
All emails, both internal and external are delivered successfully with the exception of anyone with a btinternet address. I have tested failed addresses from other Exchange servers and they send OK so it's just this server that seems to have something against BT.
I get failure messages like this:
"This message hasn't been delivered yet. Delivery will continue to be attempted.
The server will keep trying to deliver this message for the next 1 days, 19 hours and 55 minutes. You'll be notified if the message can't be delivered by that time"
I've used MX Lookup to check for any blacklisting and all is clear.
Enable logs on send connector and check the log.
Check if your domain have a reverse dns record created.