Then the spam filter is not under your control. Yahoo is all about monetizing there platform. If a spammer pays them enough they will not block it even if you mark it as spam.
Gmail has the upper hand on this with the downsides noted on the web.
-> Final fix? IMO, THUNDERBIRD would be able to block these but for some the setup of a mail app is asking too much.
Hello Everyone,
Using Lenovo G585 laptop Windows 10; Firefox 62.0.2. 64 bit with Duck Duck Go search. My main FREE email provider is Yahoo mail.
I am receiving a great deal of 'spam' advertising and the majority have the address of "ATTCustomerCare@hyperfever.com.
If the "ATT" is anything to do with AT&T, I am unable to contact them by email/find their email address to inform them or ask for assistance.
I am "blocking" them through the availability under the "More" tab in my spam folder, but it is not working and they keep returning with many others advertising other products.
Apart from using Yahoo's "Paid for" programme, does anyone have any advice on how to stop them? Most go into my Spam folder, but there are a substantial number that end up in my Inbox.
I would be very grateful to know how I can stop these from arriving,
Regards,
Colin.

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