Problem sending e-mails via Rouncube webmail

[nikosoik]

Hello to everyone,
First of all i have to apologise for my english, as they are not my native language.
I am facing a problem with my Roundcube webmail client (it is the first time i am using it for my new website).
While i can receive e-mails, it is impossible to send.
To be more specific when i press compose, and after composing my e-mail all the three tabs "Send now", "Save this draft" and "Cancel" are remaining inactive and nothing happens when pressed.
The other clients (Horde and SquirrelMail) can send e-mails without a problem.
I would aprecciate some help
Thank you

 

[cPanelMichael]

Hello

The access level you selected indicates you do not have root access to this system. Could you report this problem to your web hosting provider so they can troubleshoot this issue and determine the cause?

Thank you.