Sounds unusual. Try this: - click 'new message' - click the F9 key to display contact list - highlight desired addressses for BCC - click 'add to BCC'

You should be able to also this even without pressing F9. If adding from addressbook, the address will appear highlighted . If keying addresses directly, you can place a comma after each one.

David, I was already doing what you suggested - I tried again but it still does not work. The emails do show in the Sent, but do not come back to me & are not received by the bcc recipients. Thanks, Ron

That isn't how you described the problem. If the messages were sent and not received, it may be that your ISP is blocking because you're sending too many messages.

David, I am still waiting for my ISP to call me back. In the meantime I found the emails on web email coming back to me as spam. I think you found the root of the problem - just to get them to fix it & explain the guidelines. Thanks for your help. For some reason I do do have a spam folder on my Thunderbird. Ron

TIP: If you do this only occasionally, you might want to consider a mailing list vendor. Mailchimp allows 1,000 messages a month. With 30 recipients (assuming it's always the same), you could set up a free mailing list and would be entitled to send 33 (1000 / 30) messages a month to the group. Just a possibility... There are other vendors in that market place, not just Mailchimp.