About this video

File verification needs a paid account. BillionVerify is not affiliated with or endorsed by Proton or Tuta.

Video transcript

1. 00:00Eight domains

   Proton and Tuta addresses always come back unknown on the domains those two services run. That's eight domains. Here's why, and how to handle them in a list. Proton has four. proton.me, protonmail.com, protonmail.ch, and pm.me. Tuta has four too. tuta.com, tutanota.com, tutanota.de, and tutamail.com. Run any of them through BillionVerify and you get one answer. The ev_status column reads unknown. The reason column reads smtp_unverifiable, for all eight.

2. 00:35Why they're never valid

   On a normal domain, we ask the mail server about one recipient and read what comes back. Proton and Tuta's own domains don't give us a reply we can trust. Asking anyway wouldn't tell us whether the mailbox is there. So the check ends before that step. Labelling them valid would be invented. Labelling them invalid would be worse, because you'd throw away people who may be reading their mail. It's also quiet. Verification never sends an email, and on these eight domains it doesn't open a connection to the mail server at all.

3. 01:03Inside a mixed list

   Now take a real list. A personal address on Proton is unknown. A personal address on Tuta is unknown. A shared inbox name, like sales, stays unknown as well, not role. But a company's own domain that forwards to Proton or Tuta is different. It goes through a normal SMTP check. To pull this group out of a file, start with unknown in the status column. Narrow it to this reason. Then match the eight domains. Other unknowns stay behind, because they may need different handling. That matters, because unknown isn't one thing. A greylisted address is worth another try, and file jobs handle that on their own. A Proton or Tuta result won't move, so don't queue it for a recheck. The billing is simple. Every Proton and Tuta row that returns unknown costs zero credits, so you aren't paying for an answer you didn't get.

4. 01:48What to do with them

   Don't write these contacts off. Treat them as unconfirmed. Tag the group before you import it, so your sending tool can report on it separately. Then send as you normally would, and read the bounces for that tag. A hard bounce takes the address off your list. Delivered mail keeps it there. Other unknowns follow their own reason code. Eight domains, one status, no charge. A real send gives you the answer a mail server check can't.

5. 02:17Get started free

   20 free credits every day you use your account, up to 600 a month. No credit card required. Start at billionverify.com.

Featured in this video

• Encrypted email
• Email encryption