orlandoc

Thanks for the input! It looks like the problem has been resolved for now, but the cause is still unknown. I stopped the Virtual SMTP Server on my Exchange 2003 Server, and created a new one with the same configuration as the old one, however with a different name. After I started the service, I tested using telnet (locally). Now the RCPT message "xxx.xxx.xxx.xxx is blocked by Spamcop" was gone, and I was able to send and receive email from internal and external domains. So far so good, but like I said, I still don't know what caused the problem to begin with. The BlueGateSoftware domain is my personal email email host, which I used to test the inbound messages. Each time I sent an email to my work domain it was rejected, with the NDR showing a different IP address, all of which were stated as being blocked by Spamcop, and which appeared on several RBL servers. I have run anti-virus and malware scanners on the Exchange server repeatedly, and it appears to be clean - all the more puzzling. This weekend all machines on the network will get similar workouts, the thought being that maybe there is a machine on the network that passed a virus to the Exchange server and hijacked the SMTP service.

It appears as if all inbound messages to our domain (rrjfs.org) are being bounced back with the following message: 173.9.185.13 does not like recipient. Remote host said: 550 5.7.1 208.109.78.208 has been blocked by Spamcop Giving up on 173.9.185.13. When I test our email server locally using telnet on port 25, I get the same message stating that my INTERNAL ip address being blocked. I am now getting messages stating that my local gateway ip is being blocked by Spamcop as well. This sounds like a virus to me, but I cannot seem to find any information that matches that my sepecific problem. Help!