(view source code of guienvironment.bat as plain text)
:: Use this batch file to edit NT 4's environment values in GUI mode
:: Written by Rob van der Woude
:: Disclaimer: Changing environment variables may cause system failures!
:: Use this batch file entirely at your own risk.
:: Do not change any values unless you understand the
:: Always make a full backup before changing any system settings.
START "Environment" RUNDLL32 SHELL32,Control_RunDLL "sysdm.cpl",,2