Agent WranglersBounces and complaints
Treat permanent bounces and spam complaints as orders to stop, retry only temporary errors with growing gaps, and act only on signed delivery events.
- Recommended 4
Recommended
Stop on permanent failures and retry temporary ones
EML-32Read every bounce and SMTP reply. Suppress an address after a permanent failure for a bad mailbox, and retry only temporary failures.
Retry with backoff and give up in time
EML-33Retry temporary failures with growing gaps, and give up after a set time, then tell the sender.
Stop at the first complaint
EML-34Suppress an address at once when its owner marks your mail as spam.
Accept bounce and complaint events only when signed
EML-73Verify the signature on every bounce, complaint and unsubscribe event from your sending service before you act on it. Reject unsigned, altered or replayed events.
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