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What is ACPI?

ACPI.sys is a Windows driver. A driver is a small software program that allows your computer to communicate with hardware or connected devices. This means that a driver has direct access to the internals of the OS, hardware etc.
The free file information forum can help you determine if ACPI.sys belonging to the Windows system or an application you can trust.

Run a free scan to check for ACPI drivers in need of updating

ACPI.sys file information

The process known as ACPI Driver for NT or Microsoft ACPI Driver belongs to software Microsoft Windows Operating System or Microsoft ACPI Driver by Microsoft (www.microsoft.com).

Description: The original ACPI.sys is an important part of Windows and rarely causes problems. ACPI.sys is located in the folder C:\Windows\System32\drivers. Known file sizes on Windows 7/XP are 187,776 bytes (59% of all occurrences), 188,800 bytes and 11 more variants. http://www.file.net/process/acpi.sys.html 
The driver can be started or stopped from Services in the Control Panel or by other programs. It is a Windows system file. The program is not visible. The service has no detailed description. ACPI.sys is a Microsoft signed file. ACPI.sys seems to be a compressed file. Therefore the technical security rating is 4% dangerous, however also read the users reviews.

Recommended: Identify ACPI.sys related errors

Important: Some malware disguises itself as ACPI.sys, particularly when not located in the C:\Windows\System32\drivers folder. Therefore, you should check the ACPI.sys process on your PC to see if it is a threat. We recommend Security Task Manager for verifying your computer's security. This was one of the Top Download Picks of The Washington Post and PC World.


User Comments

makes our servers crash
automatica configuration power interface
Belongs to Microsoft Windows Operating System. ACPI Driver for Windows NT.
working of this file
Automatic Configuration Power Interface is a driver which will attempt to throttle CPU usage when temperatures get to high (and other power management operations)
  Chuck   (further information)
It is the interface between outside vendors and proprietory Windows Management Instrumentation. Can't leave home without it.
  Stephen   (further information)
takes up CPU resources when running 3D applications on some laptops
when i try to reinstall windows it says "acpi.sys corrupted". how to fix it
Lots -- by accident! This error message = defective RAM. Replace and, voila, your laptop will spark right up.
ACPI is an open standard specification introduced by industry to allow operating systems to "discover" hardware and manage power resources. It is what allows "sleep mode" and "wake on key" as well as other energy management processes. acpi.sys is Windows system driver that handles these processes.
  Elektronik_1   (further information)
nothing.. firefox was installed and reinstalled the latest update caused our pc to crash numerous times
I am investigating a virus which through AVG incorrectly states that acpi.sys is carrying a virus. Not sure of why at this stage
  Henry M  
Fingala redirection infects it and stops google working. Tdskiller.exe from Kaspersky fixed it.
Windows file needed for proper boot up.
I have the same issue with AVG, wanted to move the acpi.sys to a quarantine folder.
removed with spybot1.6.2, damaged chrome and IE, redirection to google.cz clone website, damages SSL connections and installs other malware like browser pop-ups

Rating chart

Summary: Average user rating of ACPI.sys: based on 20 votes with 16 user comments.
12 users think ACPI.sys is essential for Windows or an installed application. 5 users think it's probably harmless. One user thinks it's neither essential nor dangerous. 2 users think ACPI.sys is dangerous and recommend removing it. 6 users don't grade ACPI.sys ("not sure about it").

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ACPI scanner

Security Task Manager shows all running Windows tasks including embedded hidden functions (e.g. keyboard or browser monitoring, autostart entry). A unique security risk rating indicates the likelihood of the process being potential spyware, malware, keylogger or a Trojan.

Malwarebytes Anti-Malware detects and removes sleeping spyware, adware, trojans, keyloggers, malware and tracking threats from your hard disk. Ideal supplement to Security Task Manager.

SpeedUpMyPC scans, cleans, repairs and optimizes your computer.

Other processes

ACPI.sys [all]