I try sending e-mails to my friends, but every time I do, I get a "Mailer-Daemon Notice" in my mailbox saying that the address doesn't work. Is it a glitch?

First of all, the email address is incorrect, number two, the email is no longer in existence.

First of all, the email address has to be correct. Is it?

me too. mailer daemon is the server's name. it send notices for invalid emails. ask you freinds for correct emails