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Thunderbird will not send blind carbon copies

  • 4 replies
  • 3 have this problem
  • 1 view
  • Last reply by robtapril

robtapril
robtapril
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I am trying to send a mass email but I do not want each recipient to see the other recipients' email addresses. I have tried to send all as a BCC, or, alternatively, I have used my personal email address as primary recipient and other emails as BCC recipients but I continue to get Undeliverable messages. The BCC addresses work as primary recipients but not as BCC recipients.

I am trying to send a mass email but I do not want each recipient to see the other recipients' email addresses. I have tried to send all as a BCC, or, alternatively, I have used my personal email address as primary recipient and other emails as BCC recipients but I continue to get Undeliverable messages. The BCC addresses work as primary recipients but not as BCC recipients.

Chosen solution

Did you put in the semicolon? Whatever has returned this message seems to be mis-parsing the addresses. See where the quotes are placed?

Thunderbird works best with one address per line. If you really must stack up multiple addresses on one line, use commas to separate them.

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All Replies (4)

Matt
Matt
  • Moderator
  • Top 10 Contributor
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What is the exact error message? What mail provider?

Both are important as most sending issues of this kind are caused by two or tree issues.

1. You are sending more messages than your provider allows in one go or one hour or one day.

2. Your provider does not like the mail you are sending with so many BCC recipients and blocks it as spam.

3. Your recipients mail servers or some of them identify the message with BCC as SPAM are refuse delivery.

With the exact error message and the provider we might be able to work out which applies, or if it is one of the more infrequent causes.

robtapril
robtapril Question owner
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The exact error message is:


HE1EUR01FT056.mail.protection.outlook.com rejected your message to the following email addresses:

"ronbales1@gmail.com; robtapril"@hotmail.com A communication failure occurred during the delivery of this message. Please try to resend the message later. If the problem continues, contact your email admin.

HE1EUR01FT056.mail.protection.outlook.com gave this error: Requested action not taken: mailbox unavailable.

This was a test message. Only 2 recipients. Both sent as BCC recipients. I get similar error messages when I send to a primary recipient and 1 or 2 BCC's.

Zenos
Zenos
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Chosen Solution

Did you put in the semicolon? Whatever has returned this message seems to be mis-parsing the addresses. See where the quotes are placed?

Thunderbird works best with one address per line. If you really must stack up multiple addresses on one line, use commas to separate them.

robtapril
robtapril Question owner
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Thanks. Problem solved. I separated the emails by comma instead of semicolon. Works fine now.