IMAP/Squirrelmail problem at ubuntu intrepid

all are set based on this tutorial, but it seems i'm stuck on this problem.

i got an error like this, hoping to get a solution on this:

root@ubuntuserver:/home# tail /var/log/mail.log
Dec 19 03:36:03 ubuntuserver authdaemond: Installing libauthmysql
Dec 19 03:36:03 ubuntuserver authdaemond: Installation complete: authmysql
Dec 19 03:36:15 ubuntuserver imapd: Connection, ip=[::ffff:127.0.0.1]
Dec 19 03:36:15 ubuntuserver imapd: chdir example.com/sales/: Permission denied
Dec 19 03:43:28 ubuntuserver imapd: Connection, ip=[::ffff:127.0.0.1]
Dec 19 03:43:29 ubuntuserver imapd: chdir example.com/sales/: Permission denied
Dec 19 03:43:38 ubuntuserver imapd: Connection, ip=[::ffff:127.0.0.1]
Dec 19 03:43:38 ubuntuserver imapd: chdir example.com/sales/: Permission denied
Dec 19 03:45:47 ubuntuserver imapd: Connection, ip=[::ffff:127.0.0.1]
Dec 19 03:45:47 ubuntuserver imapd: chdir example.com/sales/: Permission denied

already change permission but still can't log on to squirrelmail webmail "ERROR: Connection dropped by IMAP server"

thank you,

 

Is the IMAP server running?
Whats the output of

Code:

netstat -tap | grep imap

 

root@ubuntuserver:/home/leonix# netstat -tap | grep imap
tcp6 0 0 [::]:imaps [::]:* LISTEN 4795/couriertcpd
tcp6 0 0 [::]:imap2 [::]:* LISTEN 4773/couriertcpd

 

What's the output of

Code:

ls -la

inside the example.com/sales/ directory?