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Thunderbird email issue

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jeff l
jeff l
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I suddenly this week cannot send email using Thunderbird (v. 140.4.0esr (64-bit)). I receive email fine. I can send email using webmail with my provider. Error message in Thunderbird is: "Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: resomta-h2p-555359.sys.comcast.net resomta-h2p-555359.sys.comcast.net ESMTP server not available (62240/216.183.125.238)." My provider says the issue is not at their end because my server settings are correct. Outgoing SMTP port is 465, connection security SSL/TLS. Operating Windows 11 v. 24H2.

I suddenly this week cannot send email using Thunderbird (v. 140.4.0esr (64-bit)). I receive email fine. I can send email using webmail with my provider. Error message in Thunderbird is: "Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: resomta-h2p-555359.sys.comcast.net resomta-h2p-555359.sys.comcast.net ESMTP server not available (62240/216.183.125.238)." My provider says the issue is not at their end because my server settings are correct. Outgoing SMTP port is 465, connection security SSL/TLS. Operating Windows 11 v. 24H2.

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