You can use either the webmail interface or an email client such as Microsoft Outlook, or Mozilla Thunderbird.
You can easily access your WebMail interface by just visiting: http://www.yourdomain.com/webmail,
where 'yourdomain.com' is your actual domain name.
If this is not working for you, it might be possible that your ISP is blocking the access to non-standard ports accessed through SSL connection. In this case, please use: http://webmail.osdedicated.com, where 'osdedicated.com' should be the name of your server (e.g. http://webmail.osdedicated.com).
Please use the full e-mail account username to login to the webmail interface or when setting your e-mail client software. Example: firstname.lastname@example.org instead of user
If you login to your webmail through the Webmail icon on your cPanel main page, you will be logged in with the default system email account. Please do not use the default email account, because very often emails send from the system email accounts are going to the Junk folders.
In order to use your email you have to create another email account with the same or different username.
To login to one of your added accounts from your cPanel, you should go to Email Accounts and then click the Access Webmail icon next to the account you wish to access. Then you should type in the password corresponding to the account and click on [Login].
You can easily send email messages via the webmail client you have chosen. Just find the [New message] button in Horde, the [Compose] button in Squirrelmail or the [Create a New Message] button in RoundCube and you will be able to start writing your message.
Make sure to SAVE your message if it is too long or you want to write it for a longerp eriod of time. The web mail program may drop the connection and you might lose your email.