I am trying to connect to a draytek 2830 over the internet. I can get to the login page but after entering the credentials they just disappear and bring back the login page. If I intentionally put in wrong credentials it states that incorrect login details. What might cause this as I have managed to login to this router before.

Try using internet explorer. I have seen Vigor login issues using Chrome and Firefox, Chrome appears especially bad if trying to connect to a router at end of VPN tunnel.

Thanks for the suggestion. I have tried IE and the same thing is happening. When I use username admin and password, the login details just disappear and bring back the login screen, but when I use Admin and password it states incorrect login details. This is happening with Firefox and Chrome as well.