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Cuireadh an snáithe seo sa chartlann. Cuir ceist nua má tá cabhair uait.

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?

Réiteach roghnaithe

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.

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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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Réiteach Roghnaithe

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.

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changing settings to SML and different port fixed it