DomailfixBounce message explainer
Got a "Mail Delivery Failed" or "Undeliverable" email? Paste it here, or just the error line such as 550 5.1.1. You will see what it means and what to do next.
Questions and answers
What is the difference between a hard and a soft bounce?
A hard bounce is permanent (the address or domain does not exist): remove the address. A soft bounce is temporary (full mailbox, server busy): it may work later.
Why do bounces matter?
Mail providers watch your bounce rate. Above about 2% your emails start going to spam. Verify lists before sending to keep it low.
Is the text I paste sent anywhere?
No. The explanation is worked out in your browser.
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