I dont think soo.
I had like a tons of spam emails to me, like TONS on gmail, cause I was dumb.
Usually, they offer the unsubscribe on bottom with very small font like HERE to unsub. Otherwise, blacklist would work also and reporting.
Last resort is to change email/make new one, just he has to check if he can change email in like facebook and other sites/games that he uses.
Well, these emails are not with subscription or etc.
I think it is called "email adress spoofing".
But as far as I can tell, from searching google, there is no way to protect against these emails. Or maybe there is?
Unsubscribing simply tells the sender/scammer that they hit a "live" email address. You will probably get even more e mail.....
Currently I am receiving two or three emails a day with the sender's name being a three letter combination of accented letters: y, p, and b. Sometimes from other alphabets.... Emails are pushing all sorts of products and services. Continually varies and I have stopped opening them to look for some constant for blocking/trashing purposes.
I set "always block" sender and the next email uses some other combination of the accented letters. Just set up another rule using part of the domain name as a means to screen out the junk emails they are sending.
Set up a disposable/secondary email address that you can use when email addresses are needed in order to sign up and access websites.
E.g., Throwaway01@......, Throwaway02@..... etc.. Dump the address when it gets too much junk coming in.
Check with your friend: agree to some code or pattern that you will use within the subject line as a means to validate the emails. If you receive an email that does not match that agreement you can simply delete the email. Or contact your friend and ask if he did indeed sent the email - and forgot the "code". I have been using that method for quite some time.
I have an elderly family member whose email address got out. She cannot "change" but it is generally easy to recognize incoming emails that are really not her. Delete without opening.
All in all - just take a defensive approach. Learn how to use the "rules" available within your email to route messages. Keep up to date on email scams and you will probably be able to spot spoofs as soon as they arrive.