ACPI Processor Aggregator Driver (acpipagr) Service Defaults in Windows 8

ACPI Processor Aggregator Device Driver by Microsoft Corporation.

Default Settings

Startup type:Manual
Display name:ACPI Processor Aggregator Driver
Service name:acpipagr
Service type:kernel
Error control:normal
Path:%SystemRoot%\System32\drivers\acpipagr.sys
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\acpipagr

Default Behavior

The ACPI Processor Aggregator Driver service is a kernel device driver. In Windows 8 it will not be started until the user starts it. If ACPI Processor Aggregator Driver fails to start, the error details are added to Windows 8 error log. When the operating system startup is complete, the user is being notified that the acpipagr service hasn't been started.

Restore Default Startup Configuration for ACPI Processor Aggregator Driver

1. Select your Windows 8 edition and update pack, and then click Download.

2. Save the Win8_acpipagr_Service_Startup.cmd file to a local storage device.

3. Run the saved file as an administrator.

4. Restart the computer.

The acpipagr service is using the acpipagr.sys file that is located in the %WinDir%\System32\drivers folder. If the file is corrupted or deleted, you can put it back in there.