Do I need to keep on blocking them, or does something in their system just say, “this guy’s blocking us, let’s just move on.”?
Sure would be nice to open up that field for more blockages! 
Thanks
Q
We have found that blocking email to @yahoo.com is much easier than blocking email to @ymail.com. Crooks, and crammers prefer ymail.com.
I’m sorry, but excuse me?
I was just wondering if I could delete my “blocked” addresses?
Thanks
Q
If you’ve used up 455 of 500 slots in your blocked address list, I’d say yeah you can start deleting them.
A lot of spam is going to be from one-off senders. If they are using someone else’s email as the FROM address, or an open relay as the SMTP server, you can hope that the open relay has been closed and that the spammer has moved on from using the unsuspecting person’s FROM address.
You can also hope that by now Yahoo has blocked repeat offenders, and mail from them doesn’t even get through to your address - it’s just disallowed from Yahoo altogether.
You may want to keep some addresses in your blocked sender list - such as addresses from which newsletters or ads are sent, and you’ve tried unsubscribing from their newsletters and advertising and they’re just not getting it done. Just keep blocking those.
For the most part, tho, blocking addresses is not a super-good method of spam blocking because a lot of the shittiest spam comes from one-off addresses. If you block a viagra ad from someone today they probably will send the same ad from some other address tomorrow. They do not give a shit that you have blocked them and “move on” - they move on anyway. But to another address.
Instead, help build Yahoo’s spam filters by marking the emails as spam. The from, sender, subject and body will be logged in the Yahoo spam filter software and when a pattern emerges the email will be blocked from Yahoo altogether.
Really, trying to stop spam by blocking addresses is like trying to eradicate your home of ants by killing them one at a time. Better to report your findings to the professionals so they can set fire to the anthill in the middle of town.
No. How would they know that you have blocked their emails? It’s purely a one-way system.
As an analogy, imagine that 9 out of 10 letters sent to your post box were junk mail and the post office offered a service where they would throw those 9 letters away and just deliver the 10th, genuine, one. Would that stop the senders bothering to send? No, as they have no idea their letters are being thrown away without being read - and they have a million times the motive to prune their mailing lists compared to spam emailers, where each email they send costs them $0.00 , near enough.
Okay! 
That one “got through”, and please excuse my “densi-tit-i-ty”, Askance!
And Zip?
Thanks for YOUR answer as well! I DO report spam on a regular basis on Yahoo.
Thanks!
Quasi
If you’re having to spend any time at all doing this, I suggest you get a Gmail account. I have to “report spam” on, maybe, one email every two months.
Yeah, seconding that. Gmail has the best spam filter I’ve ever used – by far. What a pleasure