Given that this message is used as the title for [[MediaWiki:Mailnologintext/en]] which tells the user that sending email requires a confirmed e-mail address, it should probably read "No sender address". The current text "No send address" does not make a lot of sense.

Message URL: https://translatewiki.net/w/i.php?title=Special:Translate&showMessage=mailnologin&group=core&language=nl