I know the title probably doesn't even make sense, but anyway. I downloaded PuTTY and set it up, and followed [this tutorial](http://www.howtoforge.com/how-to-configure-ssh-keys-authentication-with-putty-and-linux-server-in-5-quick-steps) to set up SSH keys so I don't have to input a user or password when logging in with SSH. I noticed that when I made a new user I used the `--disabled-password` parameter, since I wouldn't be needing it... but now when I give the user sudo powers I can't proceed as it asks me for the user's password, and I don't have one.

What do I do?