This could be a site change for security reason. Have you tried other Browser to see if you get the same issues?

Hi TTCorny, I don't understand why you would need to log in to Yahoo when you start Firefox, but you do have some extensions that may be changing how your Firefox works. Could you take a look: You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either: * Ctrl+Shift+a (Mac: Command+Shift+a) * "3-bar" menu button (or Tools menu) > Add-ons * type or paste '''about:addons''' in the address bar and press Enter/Return In the left column of the Add-ons page, click Extensions. Then cast a critical eye over the list on the right side. Any extensions Firefox installs for built-in features are hidden from this page, so everything listed here is your choice (and your responsibility) to manage. Anything unnecessary, suspicious or that you just do not remember installing or why? If in doubt, disable (or remove). Any improvement? After disabling or removing intrusive add-ons: (A) You may need to update your home page and search engine settings: * [[How to set the home page]] * [[Change your default search settings in Firefox]] (B) You may need to remove junk software on your computer, to prevent it from reinjecting unwanted extensions Our malware cleaning article could come in handy for that: [[Troubleshoot Firefox issues caused by malware]].