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Individual attachment size sendable by SMTP via Thunderbird

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Lt. Commander Data
Lt. Commander Data
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I often forward spam emails to the Anti-Phishing Working Group (APWG) in my fight against phishing. I always do so in attachment format, as APWG requests. However, if any individual attachment spam exceeds about 150K (give or take a few K's), the whole message gets rejected due to a (very) old SMTP (RFC2821) protocol limiting line length (998 relevant characters) within the message as measured by carriage return/line feed (CRLF). I think the rule is delineated as 4.5.3.1 within RFC. I can still forward such messages as attachments via Gmail, and I believe Yahoo, but not if I use Thunderbird as a suite to send. Is this a deficiency on Thunderbird's part, a bug, or something they intentionally have in place? And is there a workaround-?

I often forward spam emails to the Anti-Phishing Working Group (APWG) in my fight against phishing. I always do so in attachment format, as APWG requests. However, if any individual attachment spam exceeds about 150K (give or take a few K's), the whole message gets rejected due to a (very) old SMTP (RFC2821) protocol limiting line length (998 relevant characters) within the message as measured by carriage return/line feed (CRLF). I think the rule is delineated as 4.5.3.1 within RFC. I can still forward such messages as attachments via Gmail, and I believe Yahoo, but not if I use Thunderbird as a suite to send. Is this a deficiency on Thunderbird's part, a bug, or something they intentionally have in place? And is there a workaround-?

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