Just now I run Norton to make a full scanning and find that Trojan:Win64/Sirefef.D is on my computer, and I know it’s a kind of dangerous Trojan virus. But I don’t know how to delete it, because Norton cannot deal with it. Without the help of Norton, I don’t how to start removal. Now I feel my computer runs at a slower speed, and it takes a long time to open new tab on web browser and sometimes Internet browser crashes down directly. I think I should take action to get rid of it at once. Please help me!

Trojan:Win64/Sirefef.D Virus Description:

Trojan:Win64/Sirefef.D virus is a dangerous and infectious Trojan horse which is worldwide spread online and infiltrates more and more windows computer. Once it gets on your computer, it will sneak into system like registry editor, start-up items and change the default settings of system. And it is very cunning. In order to bypass the detection of antivirus program, it changes the location and pathway quickly, so no antivirus program can catch and remove it. This virus messes up the system and makes computer run in a malfunctioned way. This Trojan:Win64/Sirefef.D  virus can damage, disable and destroy the system important file, then your computer cannot run or many errors will happen. For example, when you start up your computer, it will not enter system with saying that computer cannot enter system due to losing following system file or cannot find the files. In this case, this virus has severely damaged the system. Besides, it blocks the Internet access by changing the DNS. For example, this webpage is not available or cannot access proxy server. As this virus can damage the crucial system program, then when you run some program, it will offer prompt telling this program is not available and so on. What’s worse, this virus can introduce other threats to computer system.  Anyway,it will do many damages on computer, so it should be removed immediately before it wreaks chaos.

Trojan:Win64/Sirefef.D virus is designed by professional cyber criminals who are qualified with IT knowledge to compromise targeted computer to steal PC user’s personal sensitive and valuable information. And cyber criminals spread this virus into the Internet worldwide to infect more and more computer and get more and more profits by tricking innocents PC users once this virus manages to access the targeted computer and help those remote hackers enter computer. Cyber criminals add this Trojan virus into malicious websites. When PC users visit those websites, this virus will automatically drop on their computers immediately. Also you need to pay attention to those free downloading programs from unlicensed sources. Those free software may be also bundled with this virus. When you install theses software, this Trojan malware also comes into computer soon as you install. Once Trojan:Win64/Sirefef.D malware infiltrates into your computer, computer will run improperly.  And you will be also frustrated by many problems due to this Trojan horse. Therefore, to avoid it entering into computer, please keep an eye on your online performance.

Some Traits about Trojan:Win64/Sirefef.D Virus

-Can slow down the performance of the computer, or even blue screen.

-Can create many junk files which occupy a lot of space in hard drive.

-Can download other malicious programs into computer, which make further damage.

-Can redirect you to pages you don’t want all the time no matter what you are doing.

-Take a long time to turn on or shut down your computer

-Your sensitive information can be stolen by hacker who can access to your computer with the help of this Trojan.

-May pretend as an anti-virus program and cheat you that computer is in dangerous, and ask you to pay to remove the threats.

Warm prompt: It’s complicated for people who are not computer savvy or not familiar with the virus to remove the Trojan. You can contact YooCare/YooSecurity PC professional online service for help:

Removal Guide for PCs with Windows OS

There is a removal guide of Trojan provided here; however, expertise is required during the process of removal, please make sure you are capable to do it by yourself.

>>>>>> Press Ctrl+Shift+Esc keys simultaneously to get the Task Manager to stop the active processes of Trojan:Win64/Sirefef.D virus. To do this, you will need to click the “Processes” tag at the top then find out suspicious processes and right click on them and select “End Process”.



>>>>>> Click “Start” menu at the lower left corner and type “regedit” in the search programs and files box and press Enter key. Then you will open the “Registry Editor”.



>>>>>> You will need to find out the suspicious registry files in the Registry Editor, They are usually located in: HKEY_LOCAL_MACHINE > SOFTWARE. You need to distinguish them from their “Name” and “Data” at the right column. All of them will be randomly distributed. If you are not good at this, ask for an expert for help.

registry editor

>>>>>> After you find out the suspicious registry files, you need to find out where the .exe files of the virus locate. Usually, they will be in the operating system drive. To open it, you will need to click Start menu > Computer & My computer. Generally speaking, the Operating System drive is Local Disk (C:).


>>>>>> Basically speaking, all the related files of Trojan:Win64/Sirefef.D virus will be located in Windows > System32. Find out all the files of the Trojan virus and delete them. Make sure that all the files you deleted are viruses, but not the files of the operating system. Any mistakes will cause data loss even system crash.


Video of Key Steps on How to Modify or Change Windows Registry:


Trojan:Win64/Sirefef.D virus can severely attack your computer once it gets on your PC. It corrupts your system files, weakens the security level of the infected computer and modifies all your key registry settings as well as disables your firewall because of its root-kit. The CPU usage percentage will become higher than before, which will cause constant blue or black screen death and system freeze. this Trojan virus helps cyber criminals remotely control the infected PC. So hackers can do anything on your PC and get any information from your computer or by tracking your online history. And users’ personal information like credit card, bank account details, log-in passwords or other financial information could be leaked out. Victims of this Trojan virus will suffer from financial loss. This Trojan must be removed as fast as possible to avoid further damages if you detect this nasty thing on your computer.

Warm prompt: If you are not computer savvy or not familiar with the virus to remove Trojan:Win64/Sirefef.D virus. You can contact YooCare/YooSecurity PC professional online service for help:

Published by Karen Lawrence & last updated on May 27, 2015 5:00 am

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