How to e-mail "undisclosed recipient?

How do I know which particular email adres of mine was adressed to receive undisclosed recipient mail? I use disposable yahoo plus adresses?

• Disposable Yahoo mail addresses should prevent spam by me disabling the right address that is attracting spam. How do I figure out in case of spam to undisclosed recipients, WHICH ...show more

• Answer:

  if you received an UNDISCLOSED RECIPIENT email it means the sender did not put anything in the TO or CC line and all addresses were placed in the BCC line...As you probably know this will hide all the email addresses from everyone. The only way to determine what address it was sent to is to reply to the message and ask the sender which address was used. =======================================... =======================================... Yahoo no longer picks the best answer. We out here would appreciate you doing it. So....when you are done receiving answers to your question please pick one as a BEST answer. Thanks. This link will show how. https://help.yahoo.com/kb/answers/SLN8284.html?impressions=true =======================================...