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error message - AUP#SNDR received on fwd email to service provider

Thunderbird Send and receive email
david replied
Robert.Pond
Robert.Pond

How to avoid: Sending of the message failed. An error occurred while sending mail. The mail server responded: message rejected . 

AUP#SNDR. Please check the message and try again.
How to avoid: Sending of the message failed. An error occurred while sending mail. The mail server responded: message rejected . AUP#SNDR. Please check the message and try again.

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david
david
  • Top 10 Contributor

Was this the complete error message? That seems shorter than most. thank you

Robert.Pond
Robert.Pond Question owner

I was trying to forward a 'phishing' email to my service provider

the complete error message is:

Sending of the message failed. An error occurred while sending mail. The mail server responded: {...My Email} message rejected. AUP#SNDR. Please check the message and try again.

david
david
  • Top 10 Contributor

I found this on AI:

The error AUP#SNDR indicates that your email was rejected by the recipient's server due to a violation of their Acceptable Use Policy, often related to spam filtering or sender authentication issues. To resolve this, check your email content and ensure your SPF and DKIM records are correctly configured.

My guess is the phishing attachment may have generated it.

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