I am currently running Firefox 40 on Windows 10. Every time I check for updates, Firefox will say that it is up-to-date, but I know it's not true because my other computers have prompted me to update. Months will go by and Firefox will still think it is up to date, even if it is an entire version back. Mozilla's website will tell me that my browser is outdated, but when I go to the help menu to check for updates, it checks and then says "Firefox is up to date." The only way to update is to download the browser again. What can I do?