Replace emailname with the sitename which will surely give more context.

htdocs/lang/en.utf8/mahara.php

@@ -483,8 +483,6 @@ $string['institutionmemberconfirmmessage'] = 'You have been added as a member of
 $string['institutionmemberrejectsubject'] = 'Institution membership request declined';
 $string['institutionmemberrejectmessage'] = 'Your request for membership of %s was declined.';
 
-$string['emailname'] = 'Mahara System'; // robot! 
-
 $string['config'] = 'Config';
 
 $string['sendmessage'] = 'Send message';

htdocs/lib/user.php

@@ -311,7 +311,7 @@ function email_user($userto, $userfrom, $subject, $messagetext, $messagehtml='',
     if (empty($userfrom)) {
         $mail->Sender = get_config('noreplyaddress');
         $mail->From = $mail->Sender;
-        $mail->FromName = get_string('emailname');
+        $mail->FromName = get_config('sitename');
         $customheaders[] = 'Precedence: Bulk'; // Try to avoid pesky out of office responses
         $messagetext .= "\n\n" . get_string('pleasedonotreplytothismessage') . "\n";
         if ($messagehtml) {