WinXP Environment Variables
+----------------------+------------------------------------------------+
|   ALLUSERSPROFILE    | Lists the location of the All Users Profile.   |
+----------------------+------------------------------------------------+
|       APPDATA        | Lists the location where applications store    |
|                      | data by default.                               |
+----------------------+------------------------------------------------+
|          CD          | Lists the current directory string.            |
+----------------------+------------------------------------------------+
|      CLIENTNAME      | List the client's NETBIOS name when connected  |
|                      | to terminal server session.                    |
+----------------------+------------------------------------------------+
|      CMDCMDLINE      | Lists the command line used to start the       |
|                      | current cmd.exe.                               |
+----------------------+------------------------------------------------+
|    CMDEXTVERSION     | Lists the version number of the current Command|
|                      | Processor Extensions.                          |
+----------------------+------------------------------------------------+
|  CommonProgramFiles  | Lists the path to the Common Files folder.     |
+----------------------+------------------------------------------------+
|     COMPUTERNAME     | Lists the name of the computer.                |
+----------------------+------------------------------------------------+
|       COMSPEC        | Lists the path to the command shell executable.|
+----------------------+------------------------------------------------+
|         DATE         | Lists the current date.                        |
+----------------------+------------------------------------------------+
|      ERRORLEVEL      | Lists the error code of the most recently used |
|                      | command.                                       |
+----------------------+------------------------------------------------+
|      HOMEDRIVE       | Lists the drive letter is connected to the     |
|                      | user's home directory.                         |
+----------------------+------------------------------------------------+
|       HOMEPATH       | Lists the full path of the user's home         |
|                      | directory.                                     |
+----------------------+------------------------------------------------+
|      HOMESHARE       | Lists the network path to the user's shared    |
|                      | home directory.                                |
+----------------------+------------------------------------------------+
|      LOGONSEVER      | Lists the name of the domain controller that   |
|                      | validated the current logon session.           |
+----------------------+------------------------------------------------+
| NUMBER_OF_PROCESSORS | Lists the number of processors installed on the|
|                      | computer.                                      |
+----------------------+------------------------------------------------+
|          OS          | Lists the name of the operating                |
|                      | system. (Windows XP and Windows 2000 list the  |
|                      | operating system as Windows_NT.)               |
+----------------------+------------------------------------------------+
|         Path         | Lists the search path for executable files.    |
+----------------------+------------------------------------------------+
|       PATHEXT        | Lists the file extensions that the operating   |
|                      | system considers to be executable.             |
+----------------------+------------------------------------------------+
|PROCESSOR_ARCHITECTURE| Lists the processor's chip architecture.       |
+----------------------+------------------------------------------------+
| PROCESSOR_IDENTFIER  | Lists the description of the processor.        |
+----------------------+------------------------------------------------+
|   PROCESSOR_LEVEL    | Lists the model number of the computer's       |
|                      | processor.                                     |
+----------------------+------------------------------------------------+
|  PROCESSOR_REVISION  | Lists the revision number of the processor.    |
+----------------------+------------------------------------------------+
|     ProgramFiles     | Lists the path to the Program Files folder.    |
+----------------------+------------------------------------------------+
|        PROMPT        | Lists the command-prompt settings for the      |
|                      | current interpreter.                           |
+----------------------+------------------------------------------------+
|        RANDOM        | Lists a random decimal number between 0 and    |
|                      | 32767.                                         |
+----------------------+------------------------------------------------+
|     SESSIONNAME      | Lists the connection and session names when    |
|                      | connected to terminal server session.          |
+----------------------+------------------------------------------------+
|     SYSTEMDRIVE      | Lists the drive containing the Windows root    |
|                      | directory.                                     |
+----------------------+------------------------------------------------+
|      SYSTEMROOT      | Lists the location of the Windows root         |
|                      | directory.                                     |
+----------------------+------------------------------------------------+
|     TEMP and TMP     | List default temporary directories for         |
|                      | applications that are available to users who   |
|                      | are currently logged on.                       |
+----------------------+------------------------------------------------+
|         TIME         | Lists the current time.                        |
+----------------------+------------------------------------------------+
|      USERDOMAIN      | Lists the name of the domain that contains the |
|                      | user's account.                                |
+----------------------+------------------------------------------------+
|       USERNAME       | Lists the name of the user currently logged on.|
+----------------------+------------------------------------------------+
|     USERPROFILE      | Lists the location of the profile for the      |
|                      | current user.                                  |
+----------------------+------------------------------------------------+
|        WINDIR        | Lists the location of the OS directory.        |
+----------------------+------------------------------------------------+
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