Hi, It works like a charm. I just tested in in any case. Did you check your spam folders of the BCC e-mail?

Yes, I checked, though checking the spam of the fifty people I sent it to may be a challenge.

Did you try it under the same conditions: several BCCs, nobody in the to?

Hi, Yes my test case is with no "To" filed and several BCC. All of the BCCs are received! Which version do you use? Maybe there is a problem with a particular version?

115.10.1

Anyways, I think my version is updated automatically.

I tried on that version as well. Cannot reproduce. Maybe there is an error send back from your server? My mails went through and I received everything.

No, I did not receive any error messages. This is why it took a few days for me to find out.

By the way a post by mountainmint earlier today seem to indicate a similar problem.

You may discover that many but not all servers will block emails that only use the bcc because it's typically used by spammers, so always put an email address in the TO field even if it's another email address which belongs to you.

So the emails could simply have been either not sent on by your smtp or blocked and killed by receiving server.

I have had the same issue for the last 3 weeks... however it's limited in what addresses it won't bcc. I have for several years bcc'd myself with all emails from my work email address, and it has worked wonderfully over the years, until about 3 weeks ago, I started not receiving back the bcc's.

If I add a different email address to the bcc line - it shows up at the additional email address, but still not to my work's email address. I checked with our IT dept, they ad me run a few tests and they said the issue was from Thunderbird, since I can bcc to my work email using Outlook.

It's not a critically important issue but it's annoying... and strange. Why would it work perfectly for years and now just suddenly stop working?

Well I guess I’m glad that I’m not the only person having a problem.

The real annoying thing is not knowing if it works or not.

@Joel, any google based email will hide the BCC if you send and receive from the same email address. @Robert as Toad-Hall said many providers now do not accept mail with no valid address in the To: some reject it in the sending to the SMTP with an error, others just let their SPAM filtering service drop the email in the bit bucket without error and yet others simply don't deliver the email to the BCC address because they consider it spam.

Things to be very clear on when dealing with delivery issues;

• Nothing in an of the email specification makes any guarantee about delivery. So SPAM tools often just drop email into a black hole without any errors or return messages.
• While just about everyone has a Spam/Junk folder these days, only about 10% of SPAM actually makes it as far as the user mailbox to go into that folder, the rest goes into that aforementioned black hole.
• Most smaller mail providers (ISP's and business email sever administrators) are no longer doing their own SPAM filtering on email and as a result really have no idea how it works or how much mail it kills.

Matt, a fantastic re-cap! Thanks.