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I am getting this message when trying to log in: Sending of username did not succeed. Mail server mail.comcast.net responded: Plaintext authentication disallow

  • 2 replies
  • 1 has this problem
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  • Last reply by Pauldt

Pauldt
Pauldt
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I attempted to log in this morning and the system prompted me to enter my Comcast email account password. I am positive I am entering it in correctly. Then, this message pops up:

Sending of username did not succeed. Mail server mail.comcast.net responded: Plaintext authentication disallowed on non-secure (SSL/TLS) connections.

How do I resolve this?

I attempted to log in this morning and the system prompted me to enter my Comcast email account password. I am positive I am entering it in correctly. Then, this message pops up: Sending of username did not succeed. Mail server mail.comcast.net responded: Plaintext authentication disallowed on non-secure (SSL/TLS) connections. How do I resolve this?

Chosen solution

I contacted Comcast directly and found the solution. They recently changed their settings. To correct the problem, go to Thunderbird's Server Settings and change the Port from 110 to 995. Change the Security Settings on the Connection Security to SSL/TLS. Problem solved.

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All Replies (2)

Toad-Hall
Toad-Hall
  • Top 25 Contributor
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In Thunderbird

  • Help > Troubleshooting Information
  • click on 'copy text to clipboard' button
  • In this forum question, right click in a 'post a Reply' text box and select 'Paste'.
  • You can remove all info on fonts and printers, but do not edit anything else.
Pauldt
Pauldt Question owner
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Chosen Solution

I contacted Comcast directly and found the solution. They recently changed their settings. To correct the problem, go to Thunderbird's Server Settings and change the Port from 110 to 995. Change the Security Settings on the Connection Security to SSL/TLS. Problem solved.