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Thunderbird Not sending emails when all recipients are Bcc

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  • 1 has this problem
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  • Last reply by david

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I am using Thunderbird 91.7.0 with windows 10. Thunderbird will not send emails when all of the addressees are listed under Bcc. I receive the following message: "The message could not be sent using Outgoing server (SMTP) outbound.att.net for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again." The sever setting is 465. If there is an email address listed under To: then the email will send to those listed under Bcc. This issue just started on 3-25-22.

Help Please. Thx Terry

I am using Thunderbird 91.7.0 with windows 10. Thunderbird will not send emails when all of the addressees are listed under Bcc. I receive the following message: "The message could not be sent using Outgoing server (SMTP) outbound.att.net for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again." The sever setting is 465. If there is an email address listed under To: then the email will send to those listed under Bcc. This issue just started on 3-25-22. Help Please. Thx Terry

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Include your own email id in TO: and it should work.