You can modify user environment variables by editing the following
You can modify system environment variables by editing the following
Session Manager \
Note that any environment variable that needs to be expanded (for example,
when you use %SYSTEM%) must be stored in the registry as a REG_EXPAND_SZ
registry value. Any values of type REG_SZ will not be expanded when read
from the registry.
Note that RegEdit.exe does not have a way to add REG_EXPAND_SZ. Use
RegEdt32.exe when editing these values manually.
However, note that modifications to the environment variables do not
result in immediate change. For example, if you start another Command
Prompt after making the changes, the environment variables will reflect the
previous (not the current) values. The changes do not take effect until you
log off and then log back on.
To effect these changes without having to log off, broadcast a
WM_SETTINGCHANGE message to all windows in the system, so that any
interested applications (such as Windows Explorer, Program Manager, Task Manager, Control
Panel, and so forth) can perform an update.
For example, on Windows NT-based systems, the following code fragment should propagate
the changes to the environment variables used in the Command Prompt:
SendMessageTimeout(HWND_BROADCAST, WM_SETTINGCHANGE, 0,
(LPARAM) "Environment", SMTO_ABORTIFHUNG,
None of the applications that ship with Windows 95 and Windows 98, including Windows Explorer and Program
Manager, respond to this message. Thus, while this article
can technically be implemented on Windows 95 and Windows 98, there is no effect except to
notify third-party applications. The only method of changing global
environment variables on Windows 95 is to modify the autoexec.bat file and