PnP ISA/EISA Bus Driver (isapnp) Service Defaults in Windows XP

PNP ISA Bus Driver by Microsoft Corporation.

Default Settings

Startup type: Boot
Display name:PnP ISA/EISA Bus Driver
Service name:isapnp
Service type:kernel
Error control:critical
Group:Boot Bus Extender
Path:%SystemRoot%\system32\DRIVERS\isapnp.sys
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\isapnp

Default Behavior

PnP ISA/EISA Bus Driver is a kernel device driver. In Windows XP it is starting before Kernel initialization. If the PnP ISA/EISA Bus Driver fails to load or initialize, the error is logged and the computer attempts to restart with the LastKnownGood configuration. If the LastKnownGood configuration fails, Windows XP startup also fails, and the boot process halts with a Stop error. If you disable this service, Windows XP will fail to start. Do NOT change this service startup configuration if your computer is working.

Restore Default Startup Configuration of PnP ISA/EISA Bus Driver

1. Run the Command Prompt.

2. Copy the commands below, paste them into the command window and press ENTER:

sc config isapnp start= boot
sc start isapnp

3. Close the command window and restart the computer.

The isapnp service is using the isapnp.sys file that is located in the C:\Windows\system32\DRIVERS directory. If the file is removed or corrupted, read this article to restore its original version from Windows XP installation media.