I have a new Postfix mail server on Arch Linux rather than Debian. I elected to go with Arch because it's always up to date / bleeding edge.

Yes, I know thats not a good thing necessarily on servers.

So I followed this guide and only did Postfix, Dovecot, SSL certificates, & Postgray. I didn't do Spamassassin or Procmail.

I didn't understand why in Postfix I had to add:

And in my 'virtual' file, I had to put:

carlwill@mydomain.tld carlwill@localhost.

If I didn't do this in main.cf and add the above in the virtual file, all mail would show:

Why do I need this? I don't understand. I though the virtual maps are for hosting virtual domains on a server? My server is mail.mydomain.tld and my mailboxes (Maildir) are all local users. Can someone explain this to me?

The output of postconf -n would be useful, in particular

mydestination
mydomain
myhostname

The top one is important and may be your issue with the 'relay access'.

Something like:
mydestination = $myhostname, localhost.$mydomain $mydomain
mydestination = $myhostname, localhost.$mydomain www.$mydomain, ftp.$mydomain

See 'man 5 postconf' for an explanation - or if you are brave try the Postfix users list if you have teflon pants and don't mind a good flaming for daring to ask a question :-)
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