Trouble shooting with squirrelmail install

can't login squirrelmail message:

the problem we didn't open port imap(143) in dovecot.
we will edit this file:

#vim /etc/dovecot/conf.d/10-master.conf
service imap-login {
  inet_listener imap {
    port = 143
    #port = 0

  }

if still can't log in please check on firewall.