How to adjust the time zone of RoundCube

In order to change the Time zone in RoundCube go to Personal Settings -> Preferences tab and select the desired Time zone from the drop down menu. Then click the Save button.

How to adjust the time zone of Horde

In Horde the Time zone can be altered via Options -> Locale and Time.
Choose the desired Time zone from the drop down menu then click the Save Options button.

How to send an HTML mail message using Horde webmail?

You can easily send email messages containing HTML code via the Horde webmail client.

To do this, log in to your Horde webmail client and click the [New message] button. In the "Message Composition" window that opens you will see the option [Switch to HTML composition]. Click it and a WYSIWYG editor will open, giving you the option to edit your text's font, size, format, to insert links and images, etc.

Once you are ready with the message, click [Send Message] to send it.

Security warnings show when accessing webmail

When accessing webmail at http://yourdomain.com/webmail you will be redirected to a SSL secured address and your connection will be encrypted. You will receive security warnings because the SSL used is a self-signed one and not a commercial one.

this warning because of the shared SSL of the server has been implemnted for that and which is suitable and you can safely disregard this warning

Can't login to webmail

Sometines you can not login to webmail on cPanel server though you are using correct credentials, in order to get this issue resolved you need server root access. Once you logged into the server fire the command :

/scripts/resetimappasswds

It must be working now.