SMTP server on Windows 7

You might have to wait until the process flushes its log buffer and writes to the log file. I know for the HTTP service you can manually flush the buffer and force it to write to file using this:

netsh http flush logbuffer

I'm looking around for something equivalent to that for the SMTP service.

EDIT:

Or, take a look at this from Steve Schofield's blog:

I was working on installing Windows Server 2008 x64 edition. I discovered the SMTP Service wasn't logging. SMTP was working and emails were going out. My install is 'custom' and installs just the modules we needed. Turns out, there is a small dependency on the ODBC logging module so the SMTP service logging would work. More importantly iislog.dll. Here are the instructions to fix and reproduce the behavior.

To correct it. I'm assuming you have the SMTP Service already installed and it's not logging.

1) Install ODBC Logging module (role service in Server Manager)

2) Stop / Start the SMTP Service

3) Verify your SMTP service is configured for logging. It's not on by default.

4) Try a local telnet test (assuming the telnet client is installed)

5) Look at your log folder.

1. As Matt alluded to, use the "Manage Your Server" screen to add the SMTP role as per these instructions.
2. You could use Windows Firewall on that server to block all outgoing traffic over port 25. Better yet, block all outbound port 25 traffic from your server's IP address at the gateway's firewall. This keeps you from crippling the server's network connection completely.

You could read up a bit on SMTP security on Windows Server 2003 with the following Microsoft KB Article 324285 (sorry, you'll have to find that one on your own; Server Fault only allows new users to post one URL per post). That article shows that you can grant or deny access to the SMTP virtual server based on IP addresses. This could be yet another alternative way of restricting mail flow to only those few places that you want to allow.