cPanel's webmail requires that IMAP be enabled

Interesting question. Looking at the sources under /usr/local/cpanel/base/3rdparty/ the applications themselves certainly seem to have defaults of localhost and port 143

The disable plaintext auth also has the following

Implying that webmail does indeed need IMAP, per the note

 

Care to share how?

Thank you!

 

Awesome thank you Eric

 

For Horde:

Edit /usr/local/cpanel/base/horde/imp/config/servers.php and change the port and protocol values as described here:

Wiki :: FAQ/Admin/Prerequisites

For Roundcube:

Edit /usr/local/cpanel/base/3rdparty/roundcube/config/main.inc.php, and edit the following line:

Code:

$rcmail_config['default_host'] = 'localhost';

This is explained here:

Howto_Config – Roundcube Webmail

Note that edits to the SquirrelMail, Roundcube and Horde configuration files can be overwritten when cPanel updates. To work around this, once you get everything working as you want, copy the files you have edited to another location, and create a /scripts/postupcp script that will copy the files back to their original locations. That way your custom edited files will still be present after each cPanel update.

 

Excellent!
Thank you so much Jared