Recently the plug and play stops working on my MacBook under Windows 7 Beta several times. I had to restart the machine just to get it to work again. It is very annoying if you are in the middle of something and you have several applications running.
I first tried to restart the Plug and Play service, but the option to stop or restart the service has been grayed out. Accidentally, I found that the plug and play started to work again after I restarted Windows Explorer.
Follow these steps to restart Windows Explorer.