Detailed Installation Process

The following steps offer a detailed description of the device installation process:

1. Windows detects that a new device is present.
2. The PnP service queries the device for identifiers.
3. Windows checks the three driver store index files-Infpub.dat, Infstore.dat, and Drvindex.dat-found under %SystemRoot%\Inf to determine whether an in-box or previously staged driver package is available for the device. If the driver was previously staged, Windows can install the driver without requiring the user to provide administrative credentials. In other words, standard users can install devices that have drivers staged in the driver store.
4. If no driver package for the device is found within the driver store, Windows recursively searches for a driver package for the device within the configured driver search locations, which in Windows 7 now includes Windows Update by default. If a suitable driver package is found, Windows confirms that the user has the permissions needed to install the device and verifies that the package has a trusted and valid digital signature. If the driver package satisfies these conditions, the package is then copied (staged) to the driver store.
5. The PnP service copies the driver files from the driver store to their final locations on the system.
6. The PnP service configures the registry so that Windows can use the new driver.
7. The PnP service starts the driver and the device becomes functional.

For more information about the device driver installation process in Windows 7, see the section titled "Enhancements to the Device Installation Experience in Windows 7" later in this tutorial.