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Send Message Error

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  • 3 have this problem
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  • Last reply by jm57

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I'm unable to send any emails from account on Thunderbird. This just started this week. All send attempts generate this Send Message Error:

Sending of the message failed. An error occurred while sending mail. The mail server responded: Please turn on SMTP Authentication in your mail client. syn-076-088-235-065.res.spectrum.com ([192.168.1.25]) [76.88.235.65]:51343 is not permitted to relay through this server without authentication.. Please check the message recipient

This error for every recipient I typically correspond with. I have my same email account loaded into Outlook on another pc and I can send emails to all recipients without error from Outlook.

Help please.

I'm unable to send any emails from account on Thunderbird. This just started this week. All send attempts generate this Send Message Error: Sending of the message failed. An error occurred while sending mail. The mail server responded: Please turn on SMTP Authentication in your mail client. syn-076-088-235-065.res.spectrum.com ([192.168.1.25]) [76.88.235.65]:51343 is not permitted to relay through this server without authentication.. Please check the message recipient This error for every recipient I typically correspond with. I have my same email account loaded into Outlook on another pc and I can send emails to all recipients without error from Outlook. Help please.

Chosen solution

Did you turn on authentication? is the email address of sender the same as the email address in SMTP server settings? Would you please post a screenshot of the SMTP settings, and one of the server settings? That info may prove helpful.

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Chosen Solution

Did you turn on authentication? is the email address of sender the same as the email address in SMTP server settings? Would you please post a screenshot of the SMTP settings, and one of the server settings? That info may prove helpful.

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My outgoing message security and authentication was off, I updated the authentication method, restarted Thunderbird and I'm sending messages again. Thank you very much!