I needed an email server simulator to test a script I’m writing (a simple email honeypot), and found GreenMail.
It’s a Java application and can thus run on Windows too:
This is the command I used:
java -Dgreenmail.setup.test.all -Dgreenmail.users=testuser1:P#ssw0rd@example.com,testuser2:P#ssw0rd@example.com -Dgreenmail.verbose -Dgreenmail.auth.disabled -jar greenmail-standalone-1.5.7.jar
This command starts all servers (SMTP, POP3, IMAP) on the default ports + 3000 (3025, 3110, …).
I configured 2 user mailboxes, enabled verbosity and disabled authentication.
To send emails to my script, I used Outlook:
Since everything is running on the same machine using localhost (127.0.0.1), I’m using Npcap so that I can capture loopback traffic with Wireshark (WinPcap can not capture loopback traffic).
Didier Stevens 