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How To Identify and Remove the MSASCuiL.exe Virus

Have you noticed your computer running slower lately? Strange new toolbar bookmarks in your browser? Getting bombarded with annoying pop-up ads? Your system may be infected with a dangerous virus disguising itself as the harmless Windows process MSASCuiL.exe. Don‘t panic – this guide will show you how to identify and safely remove the fake MSASCuiL.exe virus.

What is MSASCuiL.exe?

MSASCuiL.exe is a legitimate Windows process that displays the Windows Security icon in your taskbar and allows the program to interact with your system.

The real MSASCuiL.exe file is located here:

C:\Program Files\Windows Defender\MSASCuiL.exe

It has a tiny file size, usually around 50-100 KB. The process uses very little CPU, memory, or network bandwidth. It‘s completely harmless.

But cybercriminals often disguise viruses as real Windows files to bypass security programs. The malware is injected into the actual MSASCuiL.exe process, then hides on your computer gathering your personal data and downloading other nasty infections.

How the Fake MSASCuiL.exe Virus Spreads

This sneaky virus spreads through:

  • Malicious email attachments disguised as invoices, delivery notifications, or other files people want to open.
  • Fake "Windows Security" pop-up alerts telling you your system is infected and urging you to download malware disguised as anti-virus software.
  • Bundled with other software downloads like free games, video converters, or pirated versions of paid software. Always download from trusted sources!
  • Exploiting vulnerabilities in outdated versions of Windows, Adobe, Java, browsers, Flash, and other programs. Keep your software updated!
  • Infected ads and pop-ups on shady websites. Use an ad blocker and stick to reputable sites.
  • Attacks on public WiFi networks. Never access sensitive info or accounts on public WiFi without a VPN.

Once run, the virus injects malicious code into the real MSASCuiL.exe. It then operates silently in the background, logging your keystrokes to steal passwords, usernames, and financial info. It may also download additional malware, redirect your browser to unwanted pages, or add toolbars and annoying extensions.

Signs Your Computer is Infected

Here are some common signs of a MSASCuiL.exe virus infection:

  • Your antivirus or firewall is disabled without you doing it.
  • Your browser homepage and search engine have changed without your permission.
  • You see new toolbars, extensions, or addons installed you don‘t remember adding.
  • You‘re bombarded with pop-up ads, even on reputable sites like Google and Facebook.
  • Your computer runs much slower, especially when starting up or opening programs.
  • Unrecognized programs show up running in your Task Manager or msconfig startup list.
  • Suspicious hard drive activity, even when you aren‘t actively using your system.
  • High CPU, memory, or network usage, especially from svchost.exe or other generic Windows processes.

If you notice any of these, your computer is likely infected with malware – possibly MSASCuiL.exe or something else.

Checking for the Fake MSASCuiL.exe

To confirm the infection, check the MSASCuiL.exe file properties:

  1. Press Ctrl + Shift + Esc to open Task Manager.
  2. Go to the Details tab.
  3. Right click on any process called MSASCuiL.exe.
  4. Select "Open file location".
  5. This opens the Windows Explorer folder containing the file. Check the path.

The real MSASCuiL.exe is only located here:

C:\Program Files\Windows Defender

If the file path is anywhere else, it‘s an infected file! Also check the file size – if it‘s larger than 100 KB, it‘s definitely malware.

You can also scan your full system with antivirus software like Malwarebytes or HitmanPro to find and remove all infected MSASCuiL.exe files.

Removing the Fake MSASCuiL.exe Virus

Once you confirm the infection, removing the virus safely takes a few steps:

  1. Download and install a top-rated antivirus like Bitdefender or Kaspersky.
  2. Disconnect your computer from the internet and networks.
  3. Start your computer in Safe Mode by pressing F8 during boot up. This prevents the virus from defending itself.
  4. Run a full scan. Make sure to enable the advanced malware removal features.
  5. Delete or quarantine ANY file detected as infected – don‘t take chances. Even if Windows warns you deleting system files could cause harm, it‘s likely the malware trying to protect itself.
  6. Reboot normally and run another full scan to pick up any leftovers.
  7. Update Windows, browsers, Java, Flash, Acrobat, and other common vectors for infection.
  8. Change all your passwords, especially for email, banking, shopping, and other sensitive accounts that may have been compromised.
  9. Use a VPN and avoid public WiFi until you‘re confident your system is clean.

Following these steps should fully remove the fake MSASCuiL.exe and restore normal system operation. Do NOT attempt to manually delete files – you could damage Windows. Rely on the antivirus!

Protecting Yourself in the Future

Here are some tips to avoid MSASCuiL.exe and other malware:

  • Use a modern, paid antivirus like Norton 360 and keep it updated. The free built-in Windows Defender isn‘t enough.
  • Don‘t open attachments from people you don‘t know. Call to confirm if necessary.
  • Avoid downloading pirated games, movies, music and software. Even if your friend sends you a link!
  • Use strong passwords and enable multi-factor authentication on important accounts.
  • Keep Windows, Office, browsers, Java, Flash, and other software updated with the latest patches.
  • Be wary of fake security alerts – don‘t call the number or click on anything.
  • Use an ad and pop-up blocker like uBlock Origin to avoid malicious ads.
  • Never access financial or other sensitive accounts on public WiFi – use a trusted VPN service.

Staying vigilant is key to avoiding viruses, even tricky ones like the fake MSASCuiL.exe. But even if you do get infected, the steps in this guide will help you regain control of your computer!


Streamr Go

StreamrGo is always about privacy, specifically protecting your privacy online by increasing security and better standard privacy practices.