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Is there any way I can speak to someone to better explain my problem?

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I cannot get email all of a sudden. get the following error message: "Sending of username did not succeed. Mail server mail.comcast.net responded: Plaintext authentication disallowed on non-secure (SSL/TLS) connections." I tried to understand instructions in a forum page, but I do not get an opportunity to register a changed password on my ISP account. I am NOT expert in these matters!

I cannot get email all of a sudden. get the following error message: "Sending of username did not succeed. Mail server mail.comcast.net responded: Plaintext authentication disallowed on non-secure (SSL/TLS) connections." I tried to understand instructions in a forum page, but I do not get an opportunity to register a changed password on my ISP account. I am NOT expert in these matters!

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There is no staffed help desk for free software. Support is provided on this forum by Thunderbird users that volunteer their time to help. Go to the Thunderbird Help menu and click Troubleshooting Information. Click Copy to Clipboard. Come back here and paste that info into a reply window.