This is adding information to the question. I live outside the US and have used us.yahoo.com as my homepage for many years, so I can get stuff in English. If I change my homepage to yahoo.com, I go to yahoo in spanish, and it works fine. It seems to be that suddenly it won't use us.yahoo.com as my homepage, even though I can navigate to it by typing it in directly. So, it isn't a URL problem.

On the Settings page, could you check to make sure there is an "s" on the address in case there is a problem with the insecure-to-secure redirect: https://us.yahoo.com/

Otherwise, it's difficult to think of a reason for the difference between using the address bar and using the setting. Hmm...

Thanks for the idea and mulling. I changed the homepage to what you suggested and it didn't make a difference. I have never had the full URL like that in there before, and it always worked fine. I find it odd that it will use yahoo.com as a homepage, but not us.yahoo.com. Both work as URLs when directly typed in.