"unexpected error occurred while logging in" - Need help

I had this problem when I got a new internet provider. I was on windows 10 and I formatted my pc and went back to windows 7 and I could login just fine. When I upgraded to windows 10 again it did the same thing. I've tried everything I can think of and I even had my tech genuis brother see if he could fix it. This included messing with our routrer, changing dns, resetting dns, turning off firewalls, reinstalling, using the hextech repair tool, using the full repair, changing regions and switching back. It will stay stuck on "Authenticating..." the second time I try logging in so I really don't know what to do. My brother did find that when logging in it would go through all the steps but then it would loop or just stop with the connection. He used wireshark to see what was going on behind the scenes, and I don't know too much about that. I also contacted my internet provider of course and they said the problem could be the router but we kind of ruled that out. They couldn't find anything blocking league of legends either. And the thing is it works on my mom's computer and we are on the same network both using ethernet. So it's definitly something to do with my computer. I really wanna play league with my bro and I don't wanna be on windows 7. If there is anyway you can help please let me know. Thank you.