Hello, I'm having issues setting up a mail server... almost a full day of frustration. Any help would be hugely appreciated. I'm new to Linux but know some of the basics, enough to compile and install nginx and get it working in 45 min without trouble.

I cannot find any clear documentation or simple (BASIC) instructions that explain the process of Postfix + Courier-IMAP step by step. This is just for 1 email address for a personal website on Ubuntu 9.10

I don't need MySQL databases or spam filters or hugely complex/secure configurations. I have followed bits and pieces of about 10 tutorials and nothing works.

NS
ns1.linode.com    hooplah.com
ns2.linode.com    hooplah.com
ns3.linode.com    hooplah.com
ns4.linode.com    hooplah.com
ns5.linode.com    hooplah.com

MX
mail.hooplah.com @ 10

A/AAAA
       00.00.000.000
www    00.00.000.000
mail   00.00.000.000

Reverse DNS set

postfix main.cf

inet_interfaces = all

mydomain = hooplah.com
myhostname = mail.hooplah.com
myorigin = $mydomain
mydestination = $myhostname localhost.$mydomain $mydomain

append_dot_mydomain = no
readme_directory = no
biff = no

home_mailbox = maildir/
mailbox_size_limit = 0
message_size_limit = 0
mailbox_command =

alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases

notify_classes = bounce, delay, resource, software
delay_warning_time = 4h

smtpd_banner = $myhostname ESMTP $mail_name ($mail_version)

netcat mail.hooplah.com 143
* OK [CAPABILITY IMAP4rev1 UIDPLUS CHILDREN NAMESPACE THREAD=ORDEREDSUBJECT THREAD=REFERENCES SORT QUOTA IDLE ACL ACL2=UNION] Courier-IMAP ready. Copyright 1998-2008 Double Precision, Inc.  See COPYING for distribution information.

netcat mail.hooplah.com 25
220 mail.hooplah.com ESMTP Postfix (2.6.5)

I added a user called supercool and there's a /home/supercool/maildir directory. If I use an outside email account and send something to supercool@hoolpah.com there aren't any error messages, it just disappears. If I send a message to something fictitious like test@hooplah.com it will return the email as undeliverable. So it seems like it's accepting the address, but doesn't do anything once it receives the email.

My brain is melted. If you need any information to help troubleshoot I'll gladly provide it. Thanks for reading.

Also, when I use a email client (OS X Mail) and provide the username supercool and password, with the incoming mail server as mail.hooplah.com it gives an error stating "Logging into IMAP sever mail.hooplah.com failed"

Something that comes to mind is that you might have named the directory /home/supercool/Maildir (with a capital M), where Postfix is expecting a lowercase one as defined by $home_mailbox.

Otherwise, take a look at your mail logs (grep -C 5 supercool /var/log/mail.log). Mail for the supercool user should be handled by the local delivery daemon as the last step. There may be a useful error message in there.

Can't help you with the IMAP stuff, as I don't know it. If the Linode guides can't help you get Courier going, you may want to also consider Dovecot.

What do your Postfix logs show when you send a test message to the user that exists -- specifically the disposition of the message being accepted?

That's the first place to start.