Hello, I am trying to build a webserver using postfix and dovecot-postfix on Ubuntu 9.10. I've been working on it about 5 hours ( i did the same for last 6-7 nights ). And finally, I can send mails from my server, using Squirrelmail web client. But when I try to send mail from another address to my server ( tried from google apps based domain ), it gives an error: 554 554 5.7.1: Relay access denied Please help me ( BTW, I really researched a lot about it ) While building mail server, I followed this tutorial. Edit: I realised that I can send only from Squirrelmail, when I try to a client ( evolution ) with authentication enabled, it still says "Relay access denied".