Client wont open links

So my client have never been able to open links that will open upp a browser, and now when i log in to the client i get a pop up asking me to update my account and choose a new username to login with. With that said the button you need to press on this pop up that will redirect me to do that will not work because of my client wont open links, so i am completely locked out of the game atm. pls help

Update - I found a link on the League of Legends page that directed me to change my username as they requested and now i can get back in to the client again, BUT the problem still remains that my client wont open links that will open up a browser.