[SOLVED ]Can't create new users: Accounts.createUser() --> undefined

I solved this issue. For some reason, even though I have insecure and autopublish on, I had to still create the user on the server.

On the client:

// Signup Form Submit
Template.signup.events({
    'submit form': function(event) {
        event.preventDefault();
        var newUserData = {
          username: $('[id="username"]').val(),
          email: $('[id="email"]').val(),
          password: $('[id="password"]').val()
        };
        Meteor.call('insertUser', newUserData);
        Meteor.loginWithPassword(newUserData.email, newUserData.password);
    }
});

On the server:

// Create a new user
Meteor.methods({
  insertUser:function(newUserData){
    return Accounts.createUser(newUserData);
  }
});