| Daum Mail | |
|---|---|
| Domains | daum.net, hanmail.net |
| Mail routing | mx1.hanmail.net and its siblings. The hanmail.net name predates the Kakao merger and still fronts the infrastructure. |
| What we can resolve | We resolve some mailboxes here |
How Daum Mail answers a probe
What the server does when we open a connection and ask about one address.
- Rejections for unknown recipients do arrive, though response times are long enough that timeouts are a real share of any large batch.
- The hanmail.net domain is the older brand and carries the older accounts. Both route to the same service.
- Foreign connections are throttled, and the throttle tightens as batch size grows.
- Kakao's integration has not changed the mail infrastructure's SMTP behavior in any way we can observe from outside.
The part that catches people out
What we do about it
We give Daum a longer timeout than a fast provider would need, and where the connection still fails we report unknown with the cause. Guessing on a slow server is how a verifier turns latency into a false verdict.
Sending to Daum Mail mailboxes
Verification is one step. These are the things that decide whether the message lands.
- The Korean advertising-marker convention applies here as it does at Naver.
- The audience skews older than Naver's, which usually means higher complaint sensitivity and lower click rates.
- Kakao's messaging products dominate personal communication in this market, so email engagement is lower across the board.
One MX set behind two names
Look up daum.net and hanmail.net and you get the same four hosts, mx1 through mx4.hanmail.net (checked September 19, 2026). The newer kakao.com addresses don't share them. They answer on mx1 through mx4.kakao.com, a separate set of servers under the same parent company. So a Korean list that mixes all three domains is really two mail systems, and results from one tell you little about the other.
Say you've got 1,200 hanmail.net rows and 300 kakao.com rows, and you run a quick script of your own with a five-second timeout. If most hanmail rows fail and most kakao rows answer, the difference may simply be speed. Raise the timeout before you decide the older domain is full of dead accounts.
What a timeout costs when you read it wrong
A slow server creates a specific kind of error. The probe opens a connection, waits, gives up, and the tool has to write something in the result column. If it writes invalid, you delete a customer, and if it writes valid, you've invented a verdict. Unknown is the only entry that matches what happened, and it's the one that makes a report look unfinished, which is why some tools avoid it.
On a segment as old as hanmail.net the pull toward deleting is strong, because the rows feel stale anyway. Keep the two questions apart. Whether the mailbox exists is something a patient second pass can often answer, and unknowns aren't billed, so waiting costs nothing. The owner's attention is a different matter, and a job for your engagement data. Daum logins were folded into Kakao accounts in 2022, so a customer who never made the switch may have lost the habit of checking that inbox.
Questions people ask
Is Daum Mail still active?
Yes. It runs under Kakao and retains a substantial user base, weighted toward older users and long-held hanmail.net addresses.
Why is Daum slower to verify than Naver?
Response latency is higher and foreign connections are throttled harder, so timeouts make up a larger share of the results on any batch of size.
Should hanmail.net addresses be treated differently?
Treat them as older data. They are as likely to be technically valid as a daum.net address and considerably more likely to belong to someone who stopped checking it.