I followed the Using Postfix with Courier and MySQL on Ubuntu 9.10 (Karmic), but am having some trouble getting mail delivered.

I set up my domain and username in the database, but when I try to use mailx to send the welcome message, it does not get delivered (I assume it should show up under /home/vmail, is that correct?).

I took a look at the /var/log/mail.log log and found the following:

Feb 23 03:11:39 localhost postfix/pickup[1216]: 7498B104BF: uid=0 from=<root>
Feb 23 03:11:39 localhost postfix/cleanup[1392]: 7498B104BF: message-id=<20100223031139.7498B104BF@mydomain.com>
Feb 23 03:11:39 localhost postfix/qmgr[21034]: 7498B104BF: from=<root@mydomain.com>, size=321, nrcpt=1 (queue active)
Feb 23 03:11:39 localhost postfix/trivial-rewrite[1395]: warning: do not list domain mydomain.com in BOTH mydestination and virtual_mailbox_domains
Feb 23 03:11:39 localhost postfix/local[1396]: 7498B104BF: to=<daniel@mydomain.com>, relay=local, delay=0.05, delays=0.03/0.01/0/0.01, dsn=5.3.0, status=bounced (Command died with status 127: "procmail -a "$EXTENSION"". Command output: sh: procmail: not found )
Feb 23 03:11:39 localhost postfix/cleanup[1392]: 7CE15104C0: message-id=<20100223031139.7CE15104C0@mydomain.com>
Feb 23 03:11:39 localhost postfix/bounce[1399]: 7498B104BF: sender non-delivery notification: 7CE15104C0
Feb 23 03:11:39 localhost postfix/qmgr[21034]: 7CE15104C0: from=<>, size=2062, nrcpt=1 (queue active)
Feb 23 03:11:39 localhost postfix/trivial-rewrite[1395]: warning: do not list domain mydomain.com in BOTH mydestination and virtual_mailbox_domains
Feb 23 03:11:39 localhost postfix/qmgr[21034]: 7498B104BF: removed
Feb 23 03:11:39 localhost postfix/local[1396]: 7CE15104C0: to=<root@mydomain.com>, relay=local, delay=0.01, delays=0/0/0/0, dsn=5.3.0, status=bounced (Command died with status 127: "procmail -a "$EXTENSION"". Command output: sh: procmail: not found )
Feb 23 03:11:39 localhost postfix/qmgr[21034]: 7CE15104C0: removed

So it looks to me like it's not finding the users I set up and is bouncing the mail.

I'm pretty new at this stuff, I'd appreciate any help you can give!

(If it matters, my domain is not pointing to my Linode IP yet, but I did add mail.mydomain.com to my /etc/hosts file -- it doesn't look like it's trying to use the old mail server though because daniel@mydomain.com is a functioning email address there so shouldn't be bouncing)

Hmm, looks like it wants to use procmail, but it isn't installed.

apt-get install procmail

... should clear it up!

Ah, thank you!

Another question now, though... where should I be finding the mail after it's delivered? /home/vmail is still empty.

I don't use procmail, so this could be completely wrong, but doesn't procmail deliver the mail from the Postfix mail queue to the local users mail directory?

So /home/user/Maildir or something like this.

Try

postconf | grep -E 'spool|mailbox'

and see what home_mailbox and related configuration options are set to.

Okay, I think I figured it out. The values for myhostname and mydestination weren't set properly in my postconf and instead of using the virtual domains, postfix was just using local user accounts as mailboxes (and delivering to /var/mail/username). I fixed the configuration and now it's delivering to /home/vmail/domain/username like I believe it should be.

Thanks to everyone for their help!