How to remove the Lcass virus

Most antivirus programs identify Lcass.EXE as malware—such as Avast identifies it as Win32:Trojan-gen {Other}, and Microsoft identifies it as Worm:Win32/VB!D30D or Backdoor:Win32/Rbot.gen.

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.

Click to Run a Free Virus Scan for the Lcass.EXE malware

Lcass.EXE file information

Windows Task Manager with Lcass
Lcass.EXE process in Windows Task Manager

The process known as or Ap

appears to belong to software Microsoft or Ap or Usb Brower or Project1

by Microsoft ( or Ap or Miorosoft or Usb Brower.

Description: Lcass.EXE is not essential for Windows and will often cause problems. Lcass.EXE is located in the C:\Windows\System32 folder. Known file sizes on Windows 10/8/7/XP are 308,810 bytes (23% of all occurrences), 186,368 bytes and 8 more variants. 
It is not a Windows system file. The program is not visible. Lcass.EXE is located in the Windows folder, but it is not a Windows core file. The software listens for or sends data on open ports to a LAN or the Internet. The process starts when Windows starts (see Registry key: MACHINE\Run, MACHINE\RunServices, Run). Lcass.EXE is able to record keyboard and mouse inputs, hide itself and monitor applications. Therefore the technical security rating is 75% dangerous, however you should also read the user reviews.

Recommended: Identify Lcass.EXE related errors

If Lcass.EXE is located in the C:\Windows folder, the security rating is 70% dangerous. The file size is 135,168 bytes (66% of all occurrences) or 4,317,184 bytes. There is no information about the author of the file. The Lcass.EXE file is an unknown file in the Windows folder. The program is not visible. The application starts when Windows starts (see Registry key: MACHINE\Run, MACHINE\RunServices, Run). The Lcass.EXE file is not a Windows system file.

Important: You should check the Lcass.EXE 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

Kopiert sich als autorun.inf in externe Festplatten!
  Johannes Faber  

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

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Best practices for resolving Lcass issues

The following programs have also been shown useful for a deeper analysis: ASecurity Task Manager examines the active Lcass process on your computer and clearly tells you what it is doing. Malwarebytes' well-known Banti-malware tool tells you if the Lcass.EXE 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 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.

Other processes

Lcass.EXE [all]