In Yahoo! Mail, you cannot add an entire domain. Instead, you will need to add the specific e-mail address that the desired messages come from.

1. Click the Addresses tab.
2. Click Add Contact at the upper left.
3. Enter the e-mail address and any other details you want, then click Save.
4. If you have an e-mail message from Bally’s Atlantic City Online, from that message you can also:
5. Click Add to Address Book in the From field of the header.
6. Click Save Contact.