How to remove the mssys virus

Most antivirus programs identify mssys.dll as malware—e.g. Symantec identifies it as Trojan.Gen, and Kaspersky identifies it as Trojan.Win32.Zapchast.aews.

The free file information forum can help you find out how to remove it. If you have additional information about this file, please leave a comment or a suggestion for other users.

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Mssys.dll file information

More precise details about what the mssys.dll process belongs to are not available. This is partly because the author is not identified.

Description: Mssys.dll is not essential for Windows and will often cause problems. Mssys.dll is located in the C:\Windows folder. The file size on Windows 10/8/7/XP is 67,072 bytes. 
A .dll file (Dynamic Link Library) is a special type of Windows program containing functions that other programs can call. This .dll file can be injected to all running processes and can change or manipulate their behavior. There is no description of the program. It can change the behavior of other programs or manipulate other programs. The program has no visible window. The service has no detailed description. The program starts when Windows starts (see Registry key: AppInit_DLLs). The mssys.dll file is not a Windows system file. mssys.dll appears to be a compressed file. Therefore the technical security rating is 94% dangerous, however you should also read the user reviews.

Recommended: Identify mssys.dll related errors

Important: You should check the mssys.dll 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

Hallo. Auf einem Forum wo ich Moderator bin wurde eine Datei hochgeladen welche mit der dubiosen mssys.dll in Zusammenhang steht bzw installiert. Aus meiner Analyse heraus kann ich mit 100% sagen, dass es sich um eine Botnet + Wurm kombination handelt. Das System sollte bei Fund dringends untersucht werden und alle Usbsticks sowie SD Karten ebenfalls, da der Wurm sich auch ├╝ber diese verteilt! MFG!
  Frederic Meyer  

Summary: Average user rating of mssys.dll: based on 1 vote with 1 user comment. One user thinks mssys.dll is dangerous and recommends removing it.

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Best practices for resolving mssys issues

The following programs have also been shown useful for a deeper analysis: Security Task Manager examines the active mssys process on your computer and clearly tells you what it is doing. Malwarebytes' well-known anti-malware tool tells you if the mssys.dll on your computer displays annoying ads, slowing it down. This type of unwanted adware program is not considered by some antivirus software to be a virus and is therefore not marked for cleanup.

A clean and tidy computer is the key requirement for avoiding PC trouble. This means running a scan for malware, cleaning your hard drive using cleanmgr and sfc /scannow, uninstalling programs that you no longer need, checking for Autostart programs (using msconfig) and enabling Windows' Automatic 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 resmon 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 DISM.exe /Online /Cleanup-image /Restorehealth command. This allows you to repair the operating system without losing data.

Other processes

mssys.dll [all]