I have three mail accounts. I used one as the sender A to represent 'Becky' One as the TO recipient B to represent as 'Client' One was 'Bcc'd' C to represent 'Laura'

Sent email. Results: A retained copy in Sent folder B received email with the B email address in TO field - no mention of others receiving copies. C received email but it was a copy of the one sent to B and so the TO field did not show the Bcc'd C address it showed the B email addess.

What does this mean for the C recipient? When There is a TO email address and it is not TO you, then you were bcc'd a Copy of the one sent to B the client As the FROM would say it was the office A ' - Becky', it would be even more obvious she had been bcc'd by Becky.

Bcc means you get a copy of what was sent to B not a separate email sent to C which only has the same content, otherwise you would not know to whom the email was sent TO eg: B

Clicking on 'Reply should put sender A in the TO field and Bcc'd recipient C in the FROM field. You do not want any accidental sending to the original TO recipient 'B' , after all they may have thought the email was only sent to them and may not be amused about others seeing what they may think of as personal emails.

re :Laura received Becky's bcc email just fine, but she could not tell from the header that she had been bcc'd - In the received email...Are you saying Laura's email address was in the TO field OR did it actually have the Clients email address in the TO field? I think you will discover it had the clients email address.

So it was an email sent FROM becky TO client and received into Laura's Inbox.

If she had been a normal recipient the TO field would have Laura's email address.

You're correct - Laura's name was NOT in the TO field, the original recipient was there. My concern is that it used to be (I think) clearer that you'd been bcc'd on an email -- your name as recipient was shown as bcc: you@youremail.com on the header of the email. And yes, if Laura hits 'reply' it only replies to the original sender (Becky) but if she doesn't realize that the email was a bcc to her and instead hits 'reply all' it DOES reply to all - no warning message, no indication that you were secretly included on the original email. So, it's too easy, in my mind, to get an email & NOT see that you were bcc'd on that email. Is there any way to change the header to display bcc:you?

I've mistakenly replied to messages people sent me as attachments, forgetting they had been attachments rather than my friend's message. Embarrassing! But I digress.

Usually mail servers do not send the BCC field with any copy of the message. Usually only the sender sees the BCC field -- in the original message in their Sent Items folder.

It might be handy to have a warning somewhere near the header of the message that you are not a named recipient of the message, so most likely you were BCC'd, but it probably requires an add-on.

i think this is a setting issue, not a server issue. If I cc rather than bcc, it shows in the header as a cc'd recipient. why is the bcc not showing? i'm pretty sure that it used to...

Can you compare using your email provider's webmail interface to see whether the BCC shows there? Certainly a discrepancy would point to a difference in Thunderbird.

Good call - looking on our webmail, a cc'd email shows a cc, but a bcc'd email shows nothing but the original recipeint (no bcc line as with the cc'd email). I'll contact our hosting company and see if they can adjust this for me. (Also, this answers why it changed - we've been with this company for 2-3 years and it took me this long to notice, I think.) Thanks!

I just hit reply to all on an email I was Bcc'd on. in hindsight, and after it being pointed out to me by a somewhat angry boss, I realize that the header does give it away, but it is not exactly in your face so to speak.

Thunderbird adds warnings such as "To protect your privacy, Thunderbird has blocked remote content in this message". Could we not have something similar such as a warning stating "Please note that you were BCC'd on this thread. Press CONTINUE to reveal REPLY and REPLY TO ALL buttons"?

That would have saved my neck today.

I came across this thread as I was searching for a plugin that would present a warning to me such as the above.

Hi smudge100, it would be a great add-on, but not seeing anything quickly, you might color your own address in the To and Cc fields as a cue that all is normal, and the lack of a highlight would indicate abnormal.

In Stylish or userChrome.css (substitute your own email address):

#expandedHeader2Rows mail-emailaddress[label*="you@example.com"] {
  background-color: #ff8 !important;
}

i spent some time chatting with Dreamhost this morning. Turns out that I could enter a support ticket to see if there's anything they can do about their settings -- they pointed me to a gmail address, since apparently they don't even use their own servers. Funny, because when you are bcc'd on an email with a gmail address, you see the bcc in the header. Same with mac.com email addresses (these are two that I had handy to test). So, it is absolutely a server issue, and I don't love Dreamhost, so new hosting for us it is. I appreciate all of your help, folks.