Microsoft Accelerator Class Extension Driver - Windows 11 Service
This service exists in Windows 11 only.
Startup Type
| Windows 11 version | Home | Pro | Education | Enterprise |
|---|---|---|---|---|
| 21H2 | not exists | not exists | not exists | not exists |
| 22H2 | not exists | not exists | not exists | not exists |
| 23H2 | not exists | not exists | not exists | not exists |
| 24H2 | Manual | Manual | Manual | Manual |
Default Properties
| Display name: | Microsoft Accelerator Class Extension Driver |
| Service name: | WinAccelCx0101 |
| Type: | kernel |
| Path: | %WinDir%\system32\drivers\WinAccelCx.sys |
| Error control: | critical |
| Group: | System Bus Extender |
Default Behavior
The Microsoft Accelerator Class Extension Driver service is a kernel mode driver. If Microsoft Accelerator Class Extension Driver fails to load or initialize, the error is logged and the computer attempts to restart, using the Last Known Good configuration. If the Last Known Good configuration fails, Windows 11 startup also fails, and the boot process halts with a Stop error. If you disable this service, Windows 11 will fail to start. Do NOT change this service startup configuration if your computer is working.
Restore Default Startup Type for Microsoft Accelerator Class Extension Driver
Automated Restore
1. Select your Windows 11 edition, and then click on the Download button below.
2. Save the RestoreMicrosoftAcceleratorClassExtensionDriverWindows11.bat file to any folder on a local drive such as SSD or a hard disk.
3. Right-click the downloaded batch file and select Properties.
4. Check the Unblock checkbox and click OK.
5. Right-click the batch file again and select Run as administrator.
6. Restart the computer to save changes.
Note. Make sure that the WinAccelCx.sys file exists in the %WinDir%\system32\drivers folder. If this file is missing you can try to restore it from your Windows 11 installation media.