First steps in Dovecot; IMAP not working

[Moi]

>Two things to check:
>
 >	# What does dovecot think user "mailtest" has?
 >	doveadm user mailtest

I get this:
field   value
uid     1002
gid     8
home    /home/mailtest
mail    mbox:~/mail:INBOX=/var/mail/mailtest
system_groups_user      mailtest

 >	# The sticky bit should be set on /var/mail (you didn't mention
 >	# setting it.  It probably doesn't have bearing on this problem,
 >	# but it will make it a little more secure.
 >	chmod 1777 /var/mail

You're right, I didn't do it.

>I usually don't use this command, I look at the log file which seems to
have more details.  Try > looking there for more diagnostics.  Also, look at
your MTA's logs as well.

I'll try to locate them.
Thank you.