Connection dropped by IMAP server : When you are trying to login to email account in Roundcube Webmail client.
You may fix the issue by follow the steps below:
If you are using Roundecube check the following logs :
#tail -50 /var/cpanel/roundcube/log/errors
1. Try to restart the IMAP service
# /etc/init.d/courier-imap restart
2. Try to update the courier imap server
#/scripts/courierup –force
3. If the issue still not solve, run the command below to fix the permission for mail directory
# chown -R user:mail /home/user/mail
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