unwanted email....?!

We all know what spam is but my email address is presently being plagued with "one-off" emails which finishes off by saying you do not need to respond to this message if it is of no interest.
Much, much worse is the unwanted emails which actually give me an unsubscribe link, which does not exist. Add to that the ones where you have to type in the unsubscribe address and email them only to find minutes later that it has been returned as there is no such address. It is very frustrating. Is there a program which can refuse to accept an email, if it does not have a valid return address, just a thought.