Running Exchange 2007, SP1. One machine, all roles except Edge.Layout is like this:Internet>Firewall>Barracuda 200 Spam Firewall>Exchange 2007I can send and recieve email for one public domain with no problem. I have two receive connectors setup:one for internet email another for internal Application Server Relays. Exchange box has two NICS as well (one for internet email-192.168.2.20, one for Application Server Relay-192.168.2.10). Everything works fine. However, I need to add another public domain. I addeda new accepted authoritative domain for the new domain, created a new email policy as well. Added a new Recieve connector to accept email to the 192.168.2.10 NIC, with a new FQDN for the public domain mail name. The email from the internet for the new domain comes into the Barracuda fine, but the problem occurs when it's being sent from the Barracuda to Exchange. Exchange does not accept it. When trying to telnet from the Barracuda to 192.168.2.10 on port 25, I receive "421 4.3.2 Service not available, closing transmission channel" Even though the Barracuda's IP address is listed as being accepted in the new Receive Connector. I even tried allowing all IPs (range 0.0.0.0 - 255.255.255.255) to be allowed in the receive connector, and I still receive the same error. I would appreciate any suggestions, as this has been driving me crazy for the past week and I need to get it resolved. Thanks!

Hi,Is there a firewall enabled on the system ?If so try to disable it and test it again.Regards,Johanblog: www.johanveldhuis.nl

Thanks for your reply John. Yeah, the windows firewall was disabled a long time ago.

Anybody have any other suggestions?

Check the security the receive connector is using, make sure you have anonymous checked, also verify that you have the correct IP address that is allowed to connect to the receive connector configured.SF - MCITP:EMA, MCTS: MOSS 2007, OCS 2007, Exchange 2007

Thanks for your reply Scott. I do have anonymous checked off on the permissions tab of the receive connector. Yes, the IP address (it's the IP of the Barrauda) is correct. Now, the Barracuda can connect just fine to the first NIC (the onefor internet email-192.168.2.20), but it can't connect to the second NIC (192.168.2.10). Is a single device (in this case, the Barracuda)only allowed to connect to one NIC on Exchange or Receive Connector at a time? I wouldn't think so. Or, do you have any other suggestions on how to receive email from two seperate, public (internet) domains?

Can the Barracuda distinguish between the two seperate domains?the problem you're hitting is the IP address that the Barracuda is using to route mail qualifies for the first receive connector. I do not beleive you can configure two different receive connectors to allow a connection from the same source IP. However, you could configure another Hub Transport Server and target that hub Transport server for the other mail domain emails.SF - MCITP:EMA, MCTS: MOSS 2007, OCS 2007, Exchange 2007

Thanksagain Scottfor your reply. Got it resolved. The issue was in Barracuda. They have a "destination" field, where you put the IP address of your Exchange (or any mail) server. Well, all I had to do was put the FQDN of the Exchange box vs. the IP address, and that got mail flowing! Thank you once again for your responses!

Glad you got it working!SF - MCITP:EMA, MCTS: MOSS 2007, OCS 2007, Exchange 2007