Why Yahoo, Outlook and AOL are "Major provider"

The short answer

Yahoo, Outlook, Hotmail, Live, MSN and AOL don't let anyone confirm whether a specific mailbox exists. They do this to stop spammers from guessing addresses. Any checker that tells you otherwise for these providers is guessing.

What we do instead

Rather than marking them invalid by mistake, or dumping them in Unknown, we put them in their own Major provider group. We still check everything we can:

• the address is properly formatted,
• it isn't a throwaway address,
• it isn't a shared inbox.

Should I send to them?

Yes. These addresses are in your clean list by default, because mail to them usually delivers. The provider is real and running. What we can't tell you is whether one particular person has closed their account.

See where your contacts get their email

Your report shows how your list splits across Gmail, Yahoo, Outlook, iCloud and business domains, and how many bad addresses each group had.

Keeping them healthy

Your own sending data fills the gap. If a Yahoo or Outlook address hard-bounces when you send to it, your email tool will usually remove or suppress it automatically. Contacts who haven't opened anything in many months are also worth reviewing.