Enhanced status code

SMTP error X.6.2

Conversion required and prohibited

Updated Jul 1, 2026

The short answer

Conversion required and prohibited Common cause: Delivery requires content conversion that policy forbids

Quick fix

Change message format or conversion policy

This code is written X.6.2 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

Change message format or conversion policy

Related codes

X.6.0 Other or undefined media error X.6.1 Media not supported X.6.3 Conversion required but unsupported X.6.4 Conversion with loss performed X.6.5 Conversion failed X.6.6 Message content not available
All SMTP error codes
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