How do I modify a Policy?

Start the System Policy Editor (Start - Programs - Administrative Tools - System Policy Editor)

Select New Policy from the File menu

Double click on Local Computer

Double click on Windows NT System and the double click Logon

Click on Logon Banner until it changes to a tick

Enter a caption and text and click OK

From the File menu, select Save as

Save in the %system root%/system32/repl/Import/Scripts as NTCONFIG.POL

Close the System Policy Editor