Definition
Hard Bounce
A permanent delivery failure: the address or domain cannot receive the message.
In detail
A hard bounce means the receiver says this will not work later either: user unknown, domain does not exist, address rejected as invalid. Soft bounces are temporary; hard bounces are permanent.
Suppress hard-bounced addresses right away. Mailing them again signals poor list hygiene and hurts reputation. Do not re-import old CSV dumps without cleaning.
Reloop marks hard bounces in events and analytics so your app can stop mailing those addresses automatically.
In Reloop
How Hard Bounce shows up when you use Reloop, hosted or self-hosted.
Related
Nearby terms
Other words that often show up next to Hard Bounce.
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