I'm using the Group Policy Management Editor to add an environment variable to our Group Policy. In general, this environment variable shouldn't already exist on the host machines, but if it does, I'd like the Group Policy setting to completely replace whatever was set on the host machine.
The Environment Variable editor gives me two similar options -- Update and Replace. The help text for both is nearly identical, both saying that it will replace the variable in the specified environment.
What is the difference between these two options? Which one should I choose to accomplish what I want?