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An error occurred while sending mail. The mail server responded: Spam detected by content scanner.

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  • Last reply by christ1

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I always use Mozilla Thunderbird for email. Today, it would not send outgoing email. Any email gives me a failed message: "Sending of the message failed. An error occurred while sending mail. The mail server responded: Spam detected by content scanner. Message rejected (ID 665754780026FB52). Please check the message and try again."

My ISP insists the problem is not with their server, and I need to have Mozilla correct it.

I always use Mozilla Thunderbird for email. Today, it would not send outgoing email. Any email gives me a failed message: "Sending of the message failed. An error occurred while sending mail. The mail server responded: Spam detected by content scanner. Message rejected (ID 665754780026FB52). Please check the message and try again." My ISP insists the problem is not with their server, and I need to have Mozilla correct it.

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My ISP insists the problem is not with their server
An error occurred while sending mail. The mail server responded: Spam detected by content scanner. Message rejected (ID 665754780026FB52).

The error message is from your ISPs mail server. So they are the one causing the problem for you.

I need to have Mozilla correct it.

There is nothing Mozilla can do about it. What you could try though is

  • send email in plain text instead of HTML
  • don't use any linked files in your email signature
  • avoid attachments

None of that will actually solve the underlying problem. It's just an attempt to work around an overly sensible spam detection mechanism your ISP has implemented which generates false positives for you.

Another workaround may be to use webmail to send those problematic messages.