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I cannot send an email with Thunderbird

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I get the following error message when trying to send an email as of this morning.


"An error occurred while sending mail. The mail server responded: 5.1.0 Authentication required. Please verify that your email address is correct in your account"

I have my outgoing server configures as it says it the help menu when using comcast
I get the following error message when trying to send an email as of this morning. "An error occurred while sending mail. The mail server responded: 5.1.0 Authentication required. Please verify that your email address is correct in your account" I have my outgoing server configures as it says it the help menu when using comcast

Asịsa ahọpụtara

Error=No Authentication

Your setting - Authentication method = No Authentication

Should be normal password.

Gụọ azịza a na nghọta 👍 1

All Replies (6)

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What are you using for SMTP settings? It sounds like they are not right.

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Description: Comcast Server Name: smtp.comcast.net port: 465 User Name: <not specified> Authentication method: No authentication connection security: SSL/TLS

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Asịsa Ahọpụtara

Error=No Authentication

Your setting - Authentication method = No Authentication

Should be normal password.

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https://support.mozilla.org/en-US/kb/cannot-send-messages#w_verify-the-correct-smtp-server-is-being-used

Thank you, it did fix it, I don't know why or how it got changed, it worked fine yesterday.

The link I posted above shows to have it set to "No Authentication" ????

Thanks again.

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Unfortunately everything you read on the Internet is not true.

This is from Comcast page.

   Incoming Mail Server Name: imap.comcast.net
   Incoming Mail Server Port Number:
       Recommended: 993 with SSL ON
       Only if Needed: 143 with SSL ON
   Outgoing Mail Server Name: smtp.comcast.net
   Outgoing Mail Server Port Number:
       Recommended: 587 (SMTP)
       Only if Needed: 465 (SMTPS)
   SSL Encryption: checked
   Authentication: XFINITY username and password required

The provider configures their servers and should have the most up to date info. I happen to use Comcast so i know what they are looking for. Keep in mind that Thunderbird is a volunteer operation and some documentations is slow to be updated.

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Got it, thanks again