Run startup scripts asynchronously
Computer Configuration\Administrative Templates\System\Logon
Lets the system run startup scripts simultaneously.
Startup scripts are batch files that run before the user is invited to log on. By default, the system waits for each startup script to complete before it runs the next startup script.
If you enable this policy, the system does not coordinate the running of startup scripts. As a result, startup scripts can run simultaneously.
If you disable this policy or do not configure it, a startup script cannot run until the previous script is complete.