Enhanced status code

SMTP error X.6.6

Message content not available

Updated Jul 1, 2026

The short answer

Message content not available Common cause: Server could not retrieve externally stored content

Quick fix

Restore / access the content source and retry

This code is written X.6.6 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

Restore / access the content source and retry

Related codes

X.6.0 Other or undefined media error X.6.1 Media not supported X.6.2 Conversion required and prohibited X.6.3 Conversion required but unsupported X.6.4 Conversion with loss performed X.6.5 Conversion failed
All SMTP error codes
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