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can't send mails. error message: An error occurred while sending mail. The mail server responded: 5.7.1 Recipient address rejected: Authentication required.

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thunderbird issue - can send mails fine from webmail, but not from Thunderbird. It's blocking all outgoing messages, and giving the error message: An error occurred while sending mail. The mail server responded: 5.7.1 Recipient address rejected: Authentication required.

Please check the message recipient....  

started suddenly - was working fine a couple of days ago. Any ideas?

thunderbird issue - can send mails fine from webmail, but not from Thunderbird. It's blocking all outgoing messages, and giving the error message: An error occurred while sending mail. The mail server responded: 5.7.1 Recipient address rejected: Authentication required. Please check the message recipient.... started suddenly - was working fine a couple of days ago. Any ideas?

Asịsa ahọpụtara

Sending from webmail does not use SMTP server so trying to compare the 2 is meaningless. You need to find out what the correct SMTP server settings for your provider and make any needed changes. Wild guess is the authentication settings need updating.

Gụọ azịza a na nghọta 👍 1

All Replies (4)

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You should talk to your email provider.

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Doesn't help unfortunately. I can send mails from webmail, so it has to be an issue in Thunderbird

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Asịsa Ahọpụtara

Sending from webmail does not use SMTP server so trying to compare the 2 is meaningless. You need to find out what the correct SMTP server settings for your provider and make any needed changes. Wild guess is the authentication settings need updating.

more options

changing settings to SML and different port fixed it