Windows does not restart to make environment variable changes take effect

To modify the environment variable "PATH" as an example, after the modification is completed, enter the DOS command prompt, enter: Set Path=c:, Close the DOS window. Open the DOS window again and enter: Echo%PATH%, you can see that the PATH value set in the environment variables, properties, My computer, is already in effect.

Instead of worrying about changes in the DOS window that affect the values of environment variables, the environment variables in the DOS window are just a copy of the Windows environment variable. But modifications to the copy will cause the Windows environment variable to refresh, which is exactly what we want!

Windows does not restart to make environment variable changes take effect