ERROR: Connection dropped by IMAP server.
Common error while accessing email account via squirrel mail client on cPanel server. This error occurs due to wrong ownership of file or folder located under etc or mail directory. Here is what worked for me on cPanel server. Suppose cPanel username is xyz to fix the issue execute following commands on server.
[root@server ]#cd /home/xyz
[root@server ]#chown xyz.xyz mail -R
[root@server ]#chown xyz.mail etc -R