This may be one for the firewalls list, but I'm not entirely sure this is a firewall issue, or, at least, *entirely* a firewall issue. I'm pretty sure it's not an exim issue.
I thought I'd see if there are any troubleshooting suggestions from this obviously very experienced user base, before trying more specialized lists. I've just installed testing/unstable on my machine. I'm running behind a NAT DSL router, with iptables on my machine. I have my own domain, running its own DNS, smtp host, http host, etc. I'm using exim 4.41, compiled from source, as my MTA. I was earlier running exim 3.36-11 on another box, behind the same router, using identical port forwarding. But in the fresh install on more robust hardware, something has gone amiss. I'm pretty sure it's not exim. All the diagnostics check out for exim. I can send from and reply to local-domain addresses, using either mutt or mail. I can also send messages to the outside world. But replies (or original messages) from the outside world fall on deaf ears. Eventually, I get an "I've given up trying" message from my ISP's MTA -- except in one instance (more on that below). Here's where it gets confusing. Running nmap against my machine from outside the domain shows it is answering that Port 25 is closed. This even though, using FireStarter, I've explicitly opened Port 25. I'm *certain* I've properly forwarded Port 25 to the correct IP address for my new machine. Here's another oddity: Even though my machine replies 'closed' to Port 25 scans, I got one error reply with one message attempt from my ISP account that suggests the port isn't *entirely* closed. Thinking I might have DNS configuration problems, I tried sending a message to [EMAIL PROTECTED] (my user name and IP address substituted for this dummy address). I didn't realize at the time you had to configure exim to accept mail addressed in this fashion. I got an error message back informing me that exim had refused to forward the dotted-quad-addressed message to my account on my host. So it seems as if *something* is getting through on Port 25. It doesn't seem, though, that it's a matter of messages reaching my host and then exim failing to properly forward them locally: There are no unforwarded messages languishing on exim's input queue. Any troubleshooting ideas would be appreciated. Griff Palmer -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]