I am running 10.11.6 el capitan on my mac. I usually use gmail on chrome to send mail, but i needed to send something via MAIL and the send button is now greyed out. usually it works. Mail shows the most recent emails i send and received using GMAIL, but i can't send now using Mail. In preferences, the incoming server info is blank. the outgoing mail server: gmail is selected TLS certficate None port 993 any suggestions? what do i do?