Question: I get email in my Yahoo! inbox constantly that doesn't have the little DomainKeys icon. If Yahoo! doesn't need domain keys to allow emails in the inbox, then why should I use them in my email marketing?

Answer: While it is true that emails that don't use DomainKeys can still be received in inboxes, it is very important that all email senders use authentication standards (DomainKeys, DKIM, SPF/Sender-ID) to help ISPs and other receivers make better decisions about what to deliver.

Email authentication helps solve two very important problems for receivers:

1. It helps to identify whether or not the email is being sent legitimately or falsely.

   By using email authentication for all of your domains (this includes domains that don't send email as well as those that do), the receivers can properly tell when an email is being sent falsely, such as bot-nets, phishing scams and forgeries.

   False emails harm recipients and brands by tricking readers, and receivers work hard to prevent those types of emails from ever reaching the inbox. If you aren't properly authenticating your brand domains, the ISPs can't be certain whether or not to deliver a message and sometimes will block or filter your message incorrectly.

2. Secondly, authenticated email can have reputation data more accurately applied to it.

   If you are a responsible email sender with a good reputation, this can help your message reach the inbox more often.

   Again, this is about helping the receivers make correct delivery decisions. Reputation data are applied to all email marketing messages whether authentication is used or not, but to ensure your email reputation is properly applied to your messages, we strongly encourage you to use authentication protocols.