[ubuntu] I got rid of my User Password, and now I can't use sudo or install anything

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http://ubuntuforums.org – Hey. Today I decided to get rid of my User Password since I'm the only user of my WUBI Ubuntu installation. Now, whenever I get asked to put in my Password to run sudo or install something, I don't have a password to put in, and I can't proceed. What can I do? Now when I try creating a new password for my user, I can't click the the change button. (Hardware)