How to set a button to open an application on windows login screen

Setting a button to open an application on the Windows login screen is not a built-in feature of Windows. The login screen is designed to provide a secure environment for user authentication and does not support launching arbitrary applications.

However, if you have a specific requirement to launch an application from the login screen, you can explore custom solutions such as:

1. Customizing the login screen: You can create a custom login screen using Windows Presentation Foundation (WPF) or Universal Windows Platform (UWP) and include a button or interface element to launch your desired application. This would require building a custom login screen and replacing the default Windows login screen.

2. Using Group Policy or registry modifications: You can leverage Group Policy or modify the Windows registry to run a specific application or script during the Windows startup process. This approach would not be specific to the login screen but would launch the application after the user logs in.

It's important to note that modifying the login screen or implementing custom solutions may involve complex configuration changes and could introduce security risks. It's recommended to thoroughly evaluate the implications and potential security concerns before implementing any customizations on the login screen.