This article will explain how you can view the email message source.
The message source is the code of the email itself. You will be able to use this if you ever need to find the Headers of your email, for example. For most people, you will not require this setting, however it is always useful to know how to access your email source.
Login to the 123-mail webmail.
Click on the Email icon in the main toolbar.
In the right pane, Click on the relevant email you would like to view the source of.
Click on the Show source icon.
You will now see the source of the email in a new pop up pane.