Remove Prifass.sys Virus

This article can help you to remove Prifass.sys Virus. The step by step removal works for every version of Microsoft Windows.

The Prifass.sys virus falls under the Trojan umbrella. This nasty parasite is quite unpleasant. It enters your OS through trickery and corrupts everything. The virus alters your system settings, modifies your Registry and corrupts essential system processes. Of course, these operations have no noticeable symptoms. You are not likely to detect them in time to prevent the infection. In fact, you may not detect the Trojan at all. Very often, these types of parasites stay hidden for weeks, even months without being detected. The thing about Trojans is that they infect numerous computers and wait for further instructions. The Prifass.sys Trojan is not an exception. It communicates with a remote server and waits for specific instructions. In your situation, it’s not the Trojan you should worry about. Worry about its publishers and their intentions. What will happen to your computer depends on the hackers and their current needs. They can set the Trojan to perform various harmful tasks. Like espionage and resource theft. You are in a bad position. The Prifass.sys virus has full control of your OS and may cause irreversible damage. The longer you tolerate this intruder on board, the bigger the chance it causes serious trouble. Do not play with your luck. The risk is too high. Remove this virus the first chance you get!

Remove Prifass.sys

How did I get infected with?

You have a lot to do with the Prifass.sys infection. This Trojan cannot enter your device without your help. It lured you into allowing it on board. This parasite lurks behind fake updates, torrents, and software bundles. Of course, the good old spam emails are also part of the distribution strategy. Yet, you should not imagine corrupted files. They still exist, but your main concern should be the corrupted links. The crooks write on behalf of well-known organizations. They embed malicious links in their letters and hope for your cooperation. The crooks what you to click on the links. One click is all it takes for a virus to be downloaded. Think twice before you act! Only your caution can keep your computer virus-free. Be extremely careful with your inbox. The spam emails are the number one cause of Trojan infections. If you receive an unexpected letter, take a minute to verify the sender. You can simply enter the questionable email address into a search engine. If it was used for shady business, someone might have complained online. Also, don’t limit yourself to fast online research. If you receive a message from an organization, your bank for example, go to their official website. Compare the email addresses listed there with the one you have received a letter from. If they don’t match, delete the pretender immediately. The corrupted message may not be an email. The instant messaging platforms are quite vulnerable. Make sure you know who the sender is. The crooks hack social media accounts and use them to spread malicious messages. Therefore, all unexpected messages that contain links should be verified. Always choose caution over carelessness!

Why is this dangerous?

The Prifass.sys Trojan should not be underestimated. This intruder has unrestricted control of your OS. It can install/uninstall programs, spy on your online and offline actions, scan your personal files for sensitive information, corrupt and delete your files. After its invasion, the Trojan causes a myriad of issues. The virus may cause odd system errors, program failures, system underperformance and frequent crashes. The thing about Trojans is that they rarely come alone. The Prifass.sys virus is very likely to install other parasites such as adware, spyware, rogue apps, and even ransomware. This intruder employs stealthiness to infect your OS, but once successfully established, it interferes with every aspect of your day to day computer activities. It prevents you from using your computer normally. From random online interference to frequent system errors, this intruder ruins your user experience. Of course, you should not focus on the obvious issues. What happens in the shadows is far more worrisome. The Trojan spies on you and threatens to steal sensitive information. You wouldn’t wish the crooks to possess sensitive information about you, would you? That’s what you risk. The Trojan may steal your usernames, passwords, phone numbers, email addresses, etc. The longer this intruder remains active, the bigger the chance it steals sensitive data. Do not risk your security and privacy. Act against the Trojan! The sooner this parasite is gone, the better!

Manual Prifass.sys Removal Instructions

The Prifass.sys infection is specifically designed to make money to its creators one way or another. The specialists from various antivirus companies like Bitdefender, Kaspersky, Norton, Avast, ESET, etc. advise that there is no harmless virus.

If you perform exactly the steps below you should be able to remove the Prifass.sys infection. Please, follow the procedures in the exact order. Please, consider to print this guide or have another computer at your disposal. You will NOT need any USB sticks or CDs.

STEP 1: Track down Prifass.sys related processes in the computer memory

STEP 2: Locate Prifass.sys startup location

STEP 3: Delete Prifass.sys traces from Chrome, Firefox and Internet Explorer

STEP 4: Undo the damage done by the virus

STEP 1: Track down Prifass.sys related processes in the computer memory

  • Open your Task Manager by pressing CTRL+SHIFT+ESC keys simultaneously
  • Carefully review all processes and stop the suspicious ones.


  • Write down the file location for later reference.

Step 2: Locate Prifass.sys startup location

Reveal Hidden Files

  • Open any folder
  • Click on “Organize” button
  • Choose “Folder and Search Options”
  • Select the “View” tab
  • Select “Show hidden files and folders” option
  • Uncheck “Hide protected operating system files”
  • Click “Apply” and “OK” button

Clean Prifass.sys virus from the windows registry

  • Once the operating system loads press simultaneously the Windows Logo Button and the R key.


  • A dialog box should open. Type “Regedit”


Depending on your OS (x86 or x64) navigate to:

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run] or
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run] or

  • and delete the display Name: [RANDOM]

delete backgroundcontainer

  • Then open your explorer and navigate to: %appdata% folder and delete the malicious executable.

Clean your HOSTS file to avoid unwanted browser redirection

Navigate to %windir%/system32/Drivers/etc/host

If you are hacked, there will be foreign IPs addresses connected to you at the bottom. Take a look below:


Step 4: Undo the possible damage done by Prifass.sys

This particular Virus may alter your DNS settings.

Attention! this can break your internet connection. Before you change your DNS settings to use Google Public DNS for Prifass.sys, be sure to write down the current server addresses on a piece of paper.

To fix the damage done by the virus you need to do the following.

  • Click the Windows Start button to open the Start Menu, type control panel in the search box and select Control Panel in the results displayed above.
  • go to Network and Internet
  • then Network and Sharing Center
  • then Change Adapter Settings
  • Right-click on your active internet connection and click properties. Under the Networking tab, find Internet Protocol Version 4 (TCP/IPv4). Left click on it and then click on properties. Both options should be automatic! By default it should be set to “Obtain an IP address automatically” and the second one to “Obtain DNS server address automatically!” If they are not just change them, however if you are part of a domain network you should contact your Domain Administrator to set these settings, otherwise the internet connection will break!!!


  • Check your scheduled tasks to make sure the virus will not download itself again.

How to Permanently Remove Prifass.sys Virus (automatic) Removal Guide

Please, have in mind that once you are infected with a single virus, it compromises your whole system or network and let all doors wide open for many other infections. To make sure manual removal is successful, we recommend to use a free scanner of any professional antimalware program to identify possible virus leftovers or temporary files.

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