Environment Variables

There are a number of environment variables that will need to be set, and there are two main ways to do it. Either setting them for the current environment or so that they are always set for any new environment.

Setting Variables In Current Environment

With a command window open [Start->Run->cmd.exe], enter :

set SOME_VAR="some value"

To confirm the setting :

echo %SOME_VAR%

Setting Permanent System-Wide Variables

There are two sets of methods required, one for DOS derived environments : [Windows 95, 98 and ME], and another for NT derived environments : [NT, 2000 and XP].

Windows 95/98

The variables are usually set in the file autoexec.bat, and if you like you can edit the file you'll probably find on the C: drive.

Microsoft have kindly provided a utility that manages this for you, helping a little.

From [Start->Run] execute the program msconfig. This will open a window with a number of tabs. Select the Autoexec.bat tab. See if there is already an entry for the variable you want to set, if so select the entry and edit it, otherwise create a new entry.

Windows ME

Microsoft have tried to make the system more structured, and therefore have ended up making useful functionality difficult to find.

Select

Start->Programs->Accessories->System Tools->System Information

This brings up a window titled "Microsoft Help and Support".

Choose the Tools menu and select the system configuration utility.

Select the "Environment" tab, and either edit or create the variable as appropriate.

NT/2000/XP

Although XP is a lot more "fluffy" than 2000, it is essentially the same.

From [Start->Settings->Control Panel] double-click on System.

Alternatively the same dialog can be accessed by right-clicking on "My Computer" on either the Desktop or within an Explorer window and selecting "Properties".

Select the "Advanced" tab and then "Environment Variables".

Look for the variable in the "user variables" or "system variables" lists. Generally you will want to change the "system variable". Edit, or create New as appropriate.

Delimiter

On Windows the character ';' (semi-colon) is conventionally used to delimit lists of values set against an environment variable. The ':' (colon) cannot be used since it is used to indicate drive letters in full pathnames, eg D:\mydir\myfile.