Creating or editing a policy in script mode is the advanced way to do this, but it requires close attention to detail, as even a small typo can not only invalidate a policy, but could also cause a nasty error message to be presented to your users. You may have noticed, on the GUI policy editor, a button that says Create As Script? You can press it at any point to turn on script mode, and if you have already built a policy, it will convert it to script for you. When doing so, you will be presented with a message warning you that you will not be able to convert the script back to the GUI version. Don't be afraid to experiment, though—if you click OK and then change your mind, you can click Cancel later, and the change will not be applied to the policy.
We have already seen an example of a policy script earlier, and now it's time to delve a bit deeper. As we said, a policy is an expression that is evaluated logically, resulting in a pass or fail. When doing this...