Verified answer

Try it this way In Yahoo Classic:

After you click on Compose or Forward to open the message window, click on "To" to open your address book which is set up only for emailing.

Check the boxes (TO, BC or BCC) next to the contacts you wish to send to, go to the top of the list and click "Insert Checked Contacts." The addresses you selected will be in the fields you selected and the address book will close.

you may placed one digital mail handle interior the "TO" container. In there, you may placed your person handle. Then, to hide the checklist of addressees, placed each and all of the recipients interior the "BCC" container. Hit, deliver and you're off.