If you need to block email domains such as yahoo, gmail, hotmail, etc. then you can enable Domain Restrictions and list the domains you want to block or allow. Here's how:
Block Email Domains
If you want to block users from using specific domains:
Navigate to Prize Manager and click the Edit button on your game
Make sure Lead Capture is enabled
Enable Domain Restrictions, and set the switch to Always Block
Enter the domains you want to block from participating on the field to the right
In the example above, anyone trying to register using gmail.com, yahoo.com, and hotmail.com will not be able to play.
Allow Email Domains
You can allow a set of domains to be allowed and block anything else that is not on the list. To do this:
Navigate to Prize Manager and click the Edit button on your game
Make sure Lead Capture is enabled
Enable Domain Restrictions, and set the switch to Only Allow
Enter the domains you want to allow on the list to the right
In this example, anyone trying to register with an email domain that is not on the list will not be able to play.