What is the hierarchy of login activities user startup scripts, group policies, etc. - Windows 10

Trying to understand what is the hierarchy of login/startup scripts that trigger when a user logs in to Windows 10 and if this is impacting a local user command script in the startup from taking effect.

Have a command script that runs on user login (placed in user's startup folder), works manually, but isn't applying during login when group policies apply (this script updates a value set by a group policy).

Simple command script changes the user's notification message duration at HKCU:\Control Panel\Accessibility\MessageDuration to 5 seconds as this is overridden to 30 minutes by Group Policy.

Solution 1:

In your specific case, Startup Script will run as the OS loads and policies applied by it will be enacted UNTIL Group Policy runs. Because GP runs at logon and then at regular intervals (90 minute default, can be modified by domain configuration), the Group Policy isn't "superseding", it's just being applied after and regularly, which the Startup Script doesn't do.

When configuring a domain, it is critical to track ALL policies applying to the systems and avoid making conflicting policies, like you have. For this reason, I personally prefer to use EITHER a Startup/Logon script OR Group Policy, but not both. Or, limit the Startup or Logon script to those functions that GP cannot handle so well or easily.