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Display Name (?):

Plug and Play

Short Name (?):

PlugPlay

Executable (?):

services.exe

Library (?):

None.

Depends On (?):

None.

Supports (?):

Fax, Fax Service, Layer 2 Service, Logical Disk Manager Administrative Service, Logical Disk Manager, Messenger, Smart Card, Telephony, Windows Audio

Description (?):

Enables a computer to recognize and adapt to hardware changes with little or no user input. Stopping or disabling this service will result in system instability.

OS (?):

NT4 Workstation, 2000 Professional, XP Home/Professional, Vista Home/Business, NT4 Server, 2000 Server, Server 2003, Vista Server

Startup (?):

Default	Home	Workstation	Server	Minimal	Tweaked	Automatic
Automatic	Automatic	Automatic	Automatic	Automatic	Disabled	Disabled

Explanation (?):

The Plug and Play service is a primary component of Windows that provides the features of plug and play. This allows Windows to detect plug and play enabled devices after they have been installed physically into the Windows based computer. These features are provided through a cooperation between software vendors and hardware vendors based upon a standards specification. This service also provides background communication with plug and play devices, so it acts as a communication layer between Windows and plug and play enabled hardware. Windows NT4 makes very little use of this service as it is only minorly plug and play aware, but versions of Windows NT passed NT4 make heavy use of this service

Technically plug and play is a simplistic alert system that notifies the operating system of a hardware change, usually through the BIOS but sometimes through a hot swappable interface such as a USB root hub. Plug and Play IDs (PNPIDS) are assigned to devices through Microsoft, but for PCI, PC Cards (PCMCIA), IEEE 1394 (Firewire) and USB devices these IDs are assigned as Vendor IDs by different standards bodies, usually the owner of the specification. Each individual vendor should have its own vendor ID, and each product model should have a unqiue Product ID (PIDS) for each unique device, which are typically assigned by the vendor. The vendor ID is three characters and the product ID is 4 numbers, which composes the 7 character plug and play ID. When Windows starts it obtains a list of VIDs and PIDs and uses these to determine if new hardware has been added. If new hardware has been added then it checks its driver database for drivers that correspond to those identifiers. If it cannot locate a driver then the user is prompted to supply a driver made for that particular device. With the Plug and Play standard you can also perform manual or periodic scans for the plug and play database so that new devices can be detected when plugged in. In Windows the manual scan can be performed from within the device manager, but typically plug and play devices should be autodetected if they're installed on an interface that supports hot swappability.

This service is important to Windows operation. It should be noted that without this service Windows will lack features to detect new hardware or adapt to hardware changes, plus other Windows services that use this service to communicate with plug and play devices will fail, causing strange error messages. However, Windows will operate without this service, but the reduced functionality will make Windows unstable and fairly unusable. It is highly recommend you do not touch the runing state or the startup type of this service. Also, this service cannot be terminated while Windows is running without manually crashing it as it was never meant to stop unless the computer was rebooting.