Maximum number of recipients per email message

To help prevent spam, the maximum number of recipients per message for mail sent from mail.yourdomain.com (replace yourdomain.com with your domain) is 50.

So this limit will apply not only to webmail, but also to your local desktop email program and web application that uses mail.yourdomain.com as the outgoing mail server.

Messages with more than the maximum number of recipients will not be sent.