Go to System and Security under Control Panel.

Select System under System and Security.

Click on Advanced system settings available on the left panel; a dialog box called System Properties will pop up.

Step 1

Click on Environment Variables... available on the bottom-right corner of the dialog box; a dialog box called Environment Variables will pop up.

Step 2

NB: There are 2 sets of variables; user variables that are defined only for the logged-in user and system variables that are defined system-wide.

Step 3

Click on New or Edit for either user variables or system variables to add or modify variables in either section respectively.

Step 4