How to write an email message in RoundCube This tutorial assumes that you've already logged in to RoundCube webmail. Now let's learn how to write and send an email message. Click the Compose button. This is where you write or compose a new email message. Enter the recipient's email adddress in To field. To copy this message to another address, click the Add Cc link. Then enter the email address you wish to copy in the Copy field. You can optionally add Bcc, Reply-To and Add Followup-To email addresses. Enter the email subject in the Subject field. Then enter your message here. If you want to include one or more attachments, click the Attach button. Click the Choose Files button to locate the file, then click Upload. When ready, click the Send button. That's it! We 've successfully sent the message. Let's go take a look. Click the Sent folder. Here is the message we just sent. This is the end of the tutorial. You now know how to write and send email messages with RoundCube.