Once you have completed making any changes to your Active Directory (AD) policies, you will probably want to apply them immediately so that you can confirm they are correct.  To do this, you will need to "force" an update to occur using the commands below:

Click Start > Run...

Type cmd into the Open: input box.

Click the OK button.

Type gpupdate /force at the Command Prompt.

Check the screen for any errors and then type exit to close the window.

Now all your policy changes should be applied, so you can check they are working as expected.