You can then choose an option to reject any sign ups that are not part of the group (if you have sent invites from our site). To do this, log in to your account. From the *Created* tab, click the title or image of the sign up. When you view the sign up, locate the *Administrator's Toolbar* at the top of the page. Select *Edit Content*. Go to *Step 5: Settings*, and under *Advanced Settings* turn *On* Enhanced Security. From here, check the box to 'Reject sign ups from emails other than ones in my group'. Remember to select *Update* at the bottom of the page to save this change. If this is not enabled and someone forwards your invite or sign up link, others can sign up.