Please let me know how I can get rid of all the no-reply phishing spam emails I receive every day from INSEAD alumni c/o Yammer, all without one-click unsubscribe?

You didn't say what e-mail you use. I have several and below is an image of what I can do with my Spectrum spam e-mail. I use, Block Sender. If it's really spam, they will produce another address to send it from.

Ifyour Inbox is chuck full of garbage (AKA SPAM) and it is starting to get to you, there is a simple and very effective solution. Get a new address and delete the old one.  Send an email to the people you want to have your new address. Use BCC and you can do this in ONE email. Generally speaking, you should not expect to keep an email address forever.

Easier said than done.....

Unless the address you are using is tied to an identity that you cannot change, it is surprisingly easy. New address are easy to acquire and cost nothing. Notifying the parties you want to have the new address is easy as ONE email. The effectiveness of this solution will amaze you.

Once you have your new address, adopt new behaviours to avoid this trap.

Don’t give your email address to just anyone. If you do, you are risking getting your address on spammers’ lists. There are going to be times you have to give an email address to someone you really do not want to. Aunt Henrietta who sends you 20 a day is an example.

In my case, if I get an email addressed to a lot of people, I contact the sender and tell them not to send me any further mail unless it is address to only me. Telling them how to use BCC is an alternative.

Sometimes web pages will demand one, even though you really don’t want to hear from them. Most of those can’t really tell if the address you are entering is actually real. My favourite is ******@blockhead.com. However if you are trying to register or subscribe to something, a valid email address may be required to get access to the information. So, another good idea is to have a second email address you give to people or web pages you need to hear from but you are not sure you trust. This is the email address you should be ready to delete when it gets polluted with all kinds of garbage (AKA SPAM) in its inbox.

Sounds like you have a habit of clicking unsubscribe on all junk email you receive. Only legitimate UCE senders will honor unsubscribe requests. Spammers will send you more spam when you click unsubscribe. That seems to be the case here. Your mailbox will definitely get more spam as time goes by.