Email addresses are critical for a lot of purposes, such as the registration of users for web sites. It’s very difficult to validate email address formats as the rules are complex. It’s also not easy to know whether an email address that looks ok is actually deliverable. To find out, you can use the Hubuco service. It is available either through the web site, or by using an API. If you want to check emails when people register on your Joomla web site, use our mail check plugin. Just configure it with your Hubuco email key and nobody will be able to register unless they give a genuine, deliverable email address. Sign up for Hubuco now.