I haven't played minecraft in a while and decided to get on but noticed that I was logged out so I tried to log back in. When I tried to log in it said "Check that you're online and try again". I've reset my password and was about to reinstall the launcher but couldn't log into the website to reinstall but then the button to log in was greyed out. I've had this problem for over a couple of months since maybe it's just a glitch/bug that would fix over time. Also, I've seen this problem on the forums and it was titled as fixed but I obviously still have this problem.

FIX: I went to C:\Windows\System32\drivers\etc and deleted the all files with the title "host" as suggested by a comment with the user Kenny Yang on a post with the same issue