Windows 10 Yahoo Mail Problems

no idea with regard to your methodology or environment, Hermitkrab … however, when i log on to yahoo email:
there's talk among fellow netizens with regard to several factors … including one's a/v being the culprit … i won't point fingers anywhere.

for myself, happened just last week … unable to log into yahoo-email (firefox). no screen-cap … seems to be similar to your issue. i tried a second browser (chrome) with exact same sign-in parameters … same results. opened brave's browser … slowly typing in "mail.yahoo.com" … before completing the address, the browser offered a slightly different url … which i chose.

logged on without a hitch. immediately afterward, carefully logged off and closed the browser. i then re-opened brave's browser … copying the url which allowed me to successfully log in. i then opened up firefox … pasted the copied url into address-bar … proceeding to log in as usual. no problem this time. and, ever since that time, i have gone back to the old url … without a hitch.

the link i've always used in the past did not have the 'https' security prefix … that could have been one problem (doubtful). also couldn't be the browser. could be the a/v … however, i will never trust 'whitelisting' yahoo. honestly, i don't recall if there was a correlation between win-10 update or not. veritably, the issue could also be yahoo herself … updating servers … revising protocol … etc.

so, Hermitkrab … try the three urls listed above. after each failed attempt … i strongly suggest for you to close/quit your browser … and then reopen browser for the next attempt.

p.s. the url in parenthesis … don't pay any mind to it … s'just browser syntax.

Thanks, Panama Jack. I'm giving up completely on Yahoo. I've used it for years with no problems. I even tried to register on a Yahoo forum in order to ask questions. I couldn't even do that. I know I have 11 unread messages, but they'll be forever unread. Fortunately, my other email clients work well. So, it's goodbye Yahoo forver!

Interestingly, I found I can reach my Yahoo inbox on my iPad. So, something inherent in Windows is blocking me. At least, none of the messages were important, requiring immediate attention.

thanks for keeping us abreast of the issue. just outta' curiosity …
[ never mind the first query … the issue is moot … since i now have read your post from the other thread. ]

ref:
Needed to Uninstall VPN to Access Internet

Yahoo has always worked fine when using tunnelbear VPN.

how do you know tunnel-bear is actually doing it's job?
Good point. I've had nothing bad take place on my PC, and reading reviews online indicates it's not a bad choice. At any rate, I'm still experimenting with VPN's. I'm currently trying Windscribe and will no doubt try others, I like experimenting. That's why I have two W10 laptops. If I screw one up I'm covered.

@Hermitkrab I use ProtonVPN & Private Internet Access. I really like them both! I use them on my Windows laptops, Andriod tablets, and iPhones. And never had any major issues. I've had to tweak some settings in PIA to get better speeds but nothing that was a problem with PIA just changing stuff up. I use the free version of ProtonVPN but I'm also a paying customer of ProtonMail so I think I can use the basic version without limits other than the really high speed and TOR access. If you use them and have questions let me know.