To change from green to red, left-click on the setting and then press F7 on your keyboard. This should immediately change the solid green line to a dotted red line, indicating that the setting you have selected will be ignored when the GPO applies to the workstation.

It's easy to accidentally create a preference where you only intend to set one little thing, and then immediately click OK, forgetting that what you are actually doing is configuring a whole bunch of settings on that machine! This would happen because even though you didn't specify anything about all of the other settings inside that preference package, they are underlined in green by default. Since this is the case with many preferences, it is a good habit to utilize the F8 key when creating new preference packages, because F8 flips all green lines to red lines. Then, once they are all set to red, and therefore not applying to anything, you can selectively re-enable the key settings that you want to put into place.

In fact, here are all of the function keys that can be used within these Group Policy Preference package screens:

• F5: Enables all settings listed on the screen (sets them all to be solid green underline)
• F6: Enables one setting, the one you currently have selected (sets it to a solid green underline)
• F7: Disables one setting, the one you currently have selected (sets it to a dotted red underline)
• F8: Disables all settings listed on the screen (sets them all to be dotted red underline)

Any time that you configure a Preference package that includes many settings like this, you will want to take the time to individually assess every single one of those settings, making sure to select the appropriate action you want taken by assigning them either green or red lines. In my Folder Options example, if I only wanted to configure Show drive letters and didn't care about anything else, I would walk my way through all of the other options inside this package and set them to red dotted lines. If I forget to do this, every single one of these settings will apply to my machine when the GPO hits. To accomplish this, I opened my new folder options screen, then pressed F8 in order to disable all settings, and then selected Show drive letters and pressed F6 to re-enable only that one setting. Show drive letters would be enabled by this package, while all of the remaining settings that are shown would be ignored: