Mail Icon Not Working

[vrose]

I cannot send emails, as the mail envelope icon is not lighting up and working! Is there any other way to send emails?

 

[Kaveman]

envelope icon

is to check if you have received Mail, not to send it.

At the top of each Email is a Send button

 

[Spawn_Dooley]

In Mail.app the keyboard combination to send mail is Shift + Command + D, In Mozilla Thunderbird it is Command + Return