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550 5.0.350 Remote server returned an error -> 500 SMTP connection violates RFC5322 2.1.1 rule of 1000 characters per line. Fix your mailer.

Robert UHRIK
Robert UHRIK
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Hi folks. Again is here the annoying problem - cannot send messages...

Thunderbird 102.4.0 (32-bit version)

Receiving server response:

550 5.0.350 Remote server returned an error -> 500 SMTP connection violates RFC5322 2.1.1 rule of 1000 characters per line. Fix your mailer.

Is there any solution ?

Thank You.

Hi folks. Again is here the annoying problem - cannot send messages... Thunderbird 102.4.0 (32-bit version) Receiving server response: 550 5.0.350 Remote server returned an error -> 500 SMTP connection violates RFC5322 2.1.1 rule of 1000 characters per line. Fix your mailer. Is there any solution ? Thank You.

All Replies (2)

Stans
Stans
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I have TB 102.4.0 (64-bit) and I just tested sending a message with a single line of 1100 characters with no line break and it got sent successfully.

Are you using any add-ons?

Robert UHRIK
Robert UHRIK Question owner
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sorry for the long delay, was off...

since then, the problem wanished... or I have not used reply-to, but created new blank message instead to continue the conversation which caused problems...

My add-ons are - see picture...