Microsoft ACPIEx Driver Service Defaults in Windows 8
ACPIEx Driver by Microsoft Corporation.
Default Settings
| Startup type: | Boot |
| Display name: | Microsoft ACPIEx Driver |
| Service name: | acpiex |
| Service type: | kernel |
| Error control: | critical |
| Group: | Boot Bus Extender |
| Path: | %SystemRoot%\System32\Drivers\acpiex.sys |
| Registry key: | HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\acpiex |
Default Behavior
The Microsoft ACPIEx Driver service is a kernel device driver. In Windows 8 it is being loaded by Boot Loader before Kernel initialization. If Microsoft ACPIEx Driver fails to load or initialize, the error details should be automatically logged. Then Windows 8 is restarting the PC and attempting to use the Last Known Good configuration. If the Last Known Good configuration isn't working properly, Windows 8 startup ends with a Stop error. If you disable the acpiex service, Windows 8 will fail to start.
Dependencies
All the services listed below will not start if Microsoft ACPIEx Driver is disabled:
- Microsoft GPIO Class Extension Driver
- Serial UART Support Library
- Simple Peripheral Bus Support Library
- Serial UART Support Library
Restore Default Startup Configuration of Microsoft ACPIEx Driver
1. Run the Command Prompt as an administrator.
2. Copy the commands below, paste them into the command window and press ENTER:
sc config acpiex start= boot
sc start acpiex
3. Close the command window and restart the computer.
The acpiex service is using the acpiex.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 8 installation media.