What is mdc8021x?

Mdc8021x.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 mdc8021x.sys is a Windows system file or if it belongs to an application that you can trust.

Run a free scan to check for mdc8021x drivers in need of updating

Mdc8021x.sys file information

The process known as IEEE 802.1X Protocol Driver belongs to software AEGIS Protocol (IEEE (version 802.1x)) by Meetinghouse Data Communications (

Description: Mdc8021x.sys is not essential for the Windows OS and causes relatively few problems. Mdc8021x.sys is located in the C:\Windows\System32\drivers folder. Known file sizes on Windows 10/8/7/XP are 15,781 bytes (53% of all occurrences), 15,890 bytes, 14,037 bytes or 15,584 bytes. 
The driver can be started or stopped from Services in the Control Panel or by other programs. The program has no visible window. The file is not a Windows core file. mdc8021x.sys appears to be a compressed file. Therefore the technical security rating is 28% dangerous, however you should also read the user reviews.

Recommended: Identify mdc8021x.sys related errors

Important: Some malware disguises itself as mdc8021x.sys, particularly when not located in the C:\Windows\System32\drivers folder. Therefore, you should check the mdc8021x.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 a system file required by MiniPCI WiFi 32 bit Windows system but incompatible with 64 bit
  Michael Taplin   (further information)
The german guy is saying his WLAN USB adapter ''Sinus 1054 data'' also uses this file. And that is all he knows.
this is a linksys wireless-g usb driver
Sinus 1054 dat

Rating chart

Summary: Average user rating of mdc8021x.sys: based on 13 votes with 4 user comments. 9 users think mdc8021x.sys is essential for Windows or an installed application. 4 users think it's neither essential nor dangerous. One user is not sure about it.

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Best practices for resolving mdc8021x issues

A clean and tidy computer is the key requirement for avoiding problems with mdc8021x. 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 mdc8021x.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

mdc8021x.sys [all]