I have an Exchange Server 2007 running well for a few weeks. I needed to add an additional network adapter (with a different ip address) to the server to be used only with a backup program. Whenever I enable this additional adapter, The server sends emails using the ip address of this adapter. I just disable it and all goes back to normal. I am routing all emails to a Barracuda Spam Filter, so I get an error because I don't want to configure the ip address of the additional adapter in the spam appliance, and also because I don't want emals to be sent throught that adapter. Is there a configuration in the Exchange Server where I can configure which adapter to use when sending emails? Luis

1st, you should only have 1 default gateway in windows, are you running multiple default gateways on the 2 adapters? 2nd, you can force the send connector to use a particular IP with set-sendconnector -sourcipaddress

knightly wrote: 1st, you should only have 1 default gateway in windows, are you running multiple default gateways on the 2 adapters? 2nd, you can force the send connector to use a particular IP with set-sendconnector -sourcipaddress Additionally, you can set the network adapter priorities in the Advanced Networking like you would for a cluster's private/public as well. Could also remove your default GW assuming your backup network is on the same subnet and doesnt need to route external.

To answer both comments: 1) I have only one gateway. The second adapter, has configured only an ip and subnet mask. 2) I forced the send connector using the command provided by knightly 3) I set the order of the network adapters putting the additional network adapter in the lowest position. I am also getting additional network problems. I am writing the configuration as I have it now and some of the problems I am getting in detail. I have a network with ip range from 192.168.1.1 to 192.168.1.254. I have a barracuda spam filter appliance with ip 192.168.1.5 I have an exchange server 2007 installed on a Windows 2003 Server 64bit edition. with ip 192.168.1.3. This server is the server where I have the backup software installed on. It is also the DNS server. The server came with two network adapters, that are now configured as a team. I installed a third adapter with an ip 192.168.1.115 that is being used only by the backup software. The backup software is ArcServe 11.5. You can specify which adapter to use when making a backup. The backup is working fine with this configuration. The barracuda appliance is configured to route all incoming emails to the exchange server and the exchange server is configured to route all ougoing emails to the barracuda appliance for security reasons. It is configured to accept mails outgoing from ip 192.168.1.3 which is the mail server. When I enabled the third card my emails were getting blocked at the barracuda because it was receiving the emails from IP 192.168.1.115 and not from 192.168.1.1.3. I made all the changes indicated and still the problem persists. So in order to be able to make backups and send emails I needed to add the ip 192.168.1.115 to barracuda. Obiously this is not the right configuration but it is working. But I had a problem last week. For some reason connections to the server failed in the afternoon for no apparent reason and when Idisabled the third adapter everything went back to normal. Today I had a different problem. When I tried to browse the network to copy some files to another computer, just by clicking over the domain name, I got a message saying that I had no permissions to browse. When I disabled the third card again I was able to browse the domain computers.

Is it possible to put your backup network on a seperate subnet? Its generally considered best practiceto do so. Also it is unusuall to have 2 nics on the same subnet that are not teamed.

Yes, echoing this... Or, configure the cuda to accept SMTP from either, but I would say two NIC's on the same subnet and plugged into the SAME switch is a misconfiguration.