smtpwindows
Is it possible to control which users in a domain can connect to the Microsoft IIS SMTP server? How is this managed?
Specifically, is it possible to restrict this to a single user?
The server is in a domain, but will only be used for a single application to send mail out to a smart host, so it doesn't need to be fully functional as a mail server.
The server is running Windows Server 2008 R2 (with the IIS6 SMTP server).
I recommend using HMailServer instead as it is free and much better (finer SMTP controls, better logging/troubleshooting tools). You can disable the POP and IMAP functionality easily.
Anyway, you should be able to change the IIS SMTP binding per below. It looks like it is for inbound, but it may also work for outbound. If not, I think it might bind to the first IP address in Windows, so you can make the IP you want to be the outbound the primary IP on your system. HMailServer will let you select the IP to bind to though.
Rather than poking at a black box and wondering why it won't work, install "Network Monitor" or Wireshark on the SMTP relay machine and sniff some SMTP traffic. You'll find out in about 30 seconds why your mail is being rejected. That's going to be your path of least resistance. The box wants to tell you what's wrong, you just need to look.
Your "network engineer" should've reached for the sniffer earlier, IMO. Sniffing the traffic on the wire seems "taboo" to some people, but it's often the best way to get to the bottom of a problem in a human-readable protocol like SMTP.
Best Answer
You haven't told us what version of Windows, but here's the instructions for IIS6 on Win2k3
http://www.microsoft.com/technet/prodtechnol/WindowsServer2003/Library/IIS/58f05ef9-55a3-42b3-9f57-27fdc8723b8a.mspx?mfr=true
Set the appropriate options here. Basic auth or Windows Integrated, depending on your needs.
/Edit : I see. Yeah, I don't think it's full-featured enough to do granular security like that. Would restricting by IP work for you?
http://www.microsoft.com/technet/prodtechnol/WindowsServer2003/Library/IIS/db81ac6a-4014-4189-91a2-12632d21aa64.mspx?mfr=true