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Thunderbird E-Mail BCC

  • 1 reply
  • 1 has this problem
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  • Last reply by sfhowes

I can send out to a list with CC or TO. However, when I attempt to use BCC, I get a message:

Sending of the message failed.

The message could not be sent using Outgoing server (SMTP) smtp.mail.yahoo.com for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again

This happens with ALL my email accounts, so it MUST be something in Thunderbird. Now, I was sending out group emails this way until a few days ago. After that, this started happening.

Patrick Mower

I can send out to a list with CC or TO. However, when I attempt to use BCC, I get a message: Sending of the message failed. The message could not be sent using Outgoing server (SMTP) smtp.mail.yahoo.com for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again This happens with ALL my email accounts, so it MUST be something in Thunderbird. Now, I was sending out group emails this way until a few days ago. After that, this started happening. Patrick Mower

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