Enhanced status code

SMTP error X.7.15

Priority level too low

Updated Jul 1, 2026

The short answer

Priority level too low Common cause: Server currently refuses mail below a priority threshold

Quick fix

Increase priority if appropriate or retry later

This code is written X.7.15 because the reason is the same whether the failure is temporary (a 4 first digit) or permanent (a 5). Read the first digit of your own bounce to know which applies.

How to fix it

Increase priority if appropriate or retry later

Related codes

X.7.0 Other or undefined security status X.7.1 Delivery not authorized X.7.2 Mailing list expansion prohibited X.7.3 Security conversion required but impossible X.7.4 Security features not supported X.7.5 Cryptographic failure
All SMTP error codes
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