I am unable to use Yahoo, where one of my email accounts is

Hi Ann, are you able to login in to your email account using another browser?

Ann, could you attach any image of what you see on that page? ([[How do I create a screenshot of my problem?]]) Can you try navigating to the login page by other means? E.g. if you're opening a bookmark, or a link from history, try accessing the provider home page, and following any login links from there? This partner login seems to have two different links to sign in documented, # https://www.sky.com/help/articles/getting-started-with-sky-yahoo-mail # https://uk.help.yahoo.com/kb/sky/SLN25586.html so if you're using one route, perhaps the other would work for you? Anyway if a page shows weird errors, the best course of action is to click the shield icon next to the location bar, and "Clear cookies and site data" from there. (It might log you out and forget some previous customizations, but should be generally comparable to what you'd see if you tried to sign in via Private Window for the same service, which you can also try to see any difference.)