What is alcxwdm?

Alcxwdm.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 operating system, hardware etc. The free file information forum can help you determine if alcxwdm.sys is a Windows system file or if it belongs to an application that you can trust.

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

Alcxwdm.sys file information

The process known as Realtek AC'97 Audio Driver belongs to software Windows® WDM driver for Realtek AC'97 Audio(HRTF data Copyright (version 1994 by MIT Media Lab)) or Windows® WDM driver for Realtek AC'97 Audio by Realtek Semiconductor (

Description: Alcxwdm.sys is not essential for the Windows OS and causes relatively few problems. Alcxwdm.sys is located in the C:\Windows\System32\drivers folder. Known file sizes on Windows 10/8/7/XP are 2,279,424 bytes (17% of all occurrences), 4,122,368 bytes and 24 more variants. 
The driver can be started or stopped from Services in the Control Panel or by other programs. The program has no visible window. There is no detailed description of this service. Alcxwdm.sys is not a Windows system file. Alcxwdm.sys is a trustworthy file from Microsoft. alcxwdm.sys appears to be a compressed file. Therefore the technical security rating is 22% dangerous, however you should also read the user reviews.

Recommended: Identify alcxwdm.sys related errors

Important: Some malware disguises itself as alcxwdm.sys, particularly when not located in the C:\Windows\System32\drivers folder. Therefore, you should check the alcxwdm.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

it is for something about audio files
Avance AC'97 Audio Driver (WDM)
there is a conflict involving portcls.sys and alcxwdm.sys.

  thanh   (further information)
it has caused several errors on my system and i have always been refered to realtek. realtek! which one?
  S. Sturgeon  
it is an avance/realtek AC'97 audio driver. may or may not be "required", but it is a useful system driver if you do have it.
compatibility with windows xp
A process needed to get the Realtec '97 Audio device running, e.g. to get sound out of your computer. Not essential, but something you don't want to miss.
install the new drivers from Realtek: WDM_A400.exe
  Meaulnes Legler   (further information)
not working sound
  Magus   (further information)
driver of sound card
Audio drivers
all i know is that its missing in my PC and my audio is playing as if its fast forwarded
It causes random crashes on several of my mashines. Deleting it seems to help
I cant seem to install my sound realtek AC 97 it half installs then says can find ALCXWDM file exe can anyone please advice of what I should do
It is not dangerous at all and a part of the WDM audio driver package
  Bijan   (further information)
WDM-Driver for Realtek/Avance AC`97 onboard-chip, May cause serios BSODs.
its a problem causes blue screen and freezing
  mike greenfield  
AC97 Audio driver. don't delete harmful
c'est un logiciel de son
  modeste adou  
my sound driver not working with out this
sound driver for asus board

Rating chart

Summary: Average user rating of alcxwdm.sys: based on 51 votes with 24 user comments. 28 users think alcxwdm.sys is essential for Windows or an installed application. 14 users think it's probably harmless. 2 users think it's neither essential nor dangerous. 4 users suspect danger. 3 users think alcxwdm.sys is dangerous and recommend removing it. 6 users don't grade alcxwdm.sys ("not sure about it").

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Best practices for resolving alcxwdm issues

A clean and tidy computer is the key requirement for avoiding problems with alcxwdm. This means running a scan for malware, cleaning your hard drive using 1cleanmgr and 2sfc /scannow, 3uninstalling programs that you no longer need, checking for Autostart programs (using 4msconfig) and enabling Windows' 5Automatic Update. Always remember to perform periodic backups, or at least to set restore points.

Should you experience an actual problem, try to recall the last thing you did, or the last thing you installed before the problem appeared for the first time. Use the 6resmon command to identify the processes that are causing your problem. Even for serious problems, rather than reinstalling Windows, you are better off repairing of your installation or, for Windows 8 and later versions, executing the 7DISM.exe /Online /Cleanup-image /Restorehealth command. This allows you to repair the operating system without losing data.

To help you analyze the alcxwdm.sys process on your computer, the following programs have proven to be helpful: ASecurity Task Manager displays all running Windows tasks, including embedded hidden processes, such as keyboard and browser monitoring or Autostart entries. A unique security risk rating indicates the likelihood of the process being potential spyware, malware or a Trojan. BMalwarebytes Anti-Malware detects and removes sleeping spyware, adware, Trojans, keyloggers, malware and trackers from your hard drive.

Other processes

alcxwdm.sys [all]