This question already has an answer here:
If an email I received mentions that copying or forwarding the email is forbidden, can I still legally do so?
For example, here is a typical disclaimer some of the emails I received contain:
If the reader of this message is not the intended recipient, or the employee or agent responsible for delivery to the intended recipient, you are hereby notified that any dissemination, distribution, or copying of this communication is STRICTLY PROHIBITED.
Is that prohibition legally enforceable in the United States?
If state-specific, I am mostly interested in the case where I am located in California, New York or Massachusetts.