Final answer:
When Windows notices a new device, it first scans it for viruses and then places it in an existing device category in Device Manager.
Step-by-step explanation:
When Windows notices that a new device has been connected, the first thing it will do is scan the device for viruses. This is an important security measure to ensure that the newly connected device does not contain any malicious software that could harm the computer system. After scanning for viruses, Windows will then place the new device in an existing device category in Device Manager.
Learn more about The process of connecting a new device to Windows