Defender ransomware (Virus Removal Instructions) - Decryption Steps Included

Defender virus Removal Guide

What is Defender ransomware?

Defender ransomware appends .defender file extension to locked files

A picture of Defender ransomware lock screen

Defender ransomware is a file-encrypting ransomware[1] virus, which has been revealed in February 2018. Malware locks most of the file types on infected computer by appending the .defender file extension to each of them. Defender virus then changes desktop's background to white brick wallpaper impersonating Windows Defender and generates a ransom note, which is downloaded from @zippyshare.

Security experts are currently testing this new ransomware and confirmed that Defender ransomware decryptor is not available yet. Neither free nor paid. Criminals lock personal files but do not ask for a ransom or anything else. They merely render the data useless and do not generate a key to decrypt them. That's how .defender virus ransom note looks like:

Your files have been encrypted by Defender Ransomware. The wall will not fall.This ransomware is not decryptable. Sorry about that.

Like most other infamous ransomware virus does, Defender virus is also distributed via spam email[2] attachments, which can be named like Microsoft visual C# v7.0 / Basic .NET. Once installed, the virus runs an executable file MpCmdRun.exe and starts the encryption procedure. In addition to that, it can also:

  • Create a resource fork (ADS) file to hide data and prevent detection;
  • Modify file/console tracing settings to hide footprints;
  • Read the active computer name;
  • Modify auto-execute functionality by setting/creating value in the registry;
  • Contact random Domain Names;
  • Mark files for removal;
  • Open files with deletion access rights;
  • Remove Shadow Volume Copies, etc.

Nevertheless, Defender ransomware virus should not intimidate you. Most of professional AV engines can detect it, so you should remove Defender ransomware with FortectIntego, SpyHunter 5Combo Cleaner or Malwarebytes and then try to restore your files from backups.
If, however, you don't have backups for important files, data decryption may be complicated or even impossible. As

Showing Defender ransomware virusDefender ransomware locks files and then appends .defender file extension to all of them. It's currently not decryptable

pointed out by ransomware experts, this virus does not have a decryptor – neither free nor paid.
Nevertheless, Defender ransomware removal is inevitable. Otherwise, extortionists can use it for transmission of other high-severity malware, which may render your PC useless.

Criminals often spend much time while trying to develop techniques which would allow them to infect computers easily. So far, the crooks have highly beloved malspam campaigns. They send fraudulent emails letters with malicious attachments inside. This way people are tricked to install ransomware by themselves.

The peculiarities of ransomware distribution

Criminals are looking for various security breaches to inject ransomware virus onto PCs. However, that's not a difficult task because OS, software, and service developers keep unifying their strengths against ransomware attacks.

Despite the fact that new techniques been found, crooks prefer malspam campaigns. All they have to do is to prepare a list of emails and send a fraudulent email letter with malicious attachment expecting that someone will fall for the trick. If someone attempts to open the attachment, he or she is asked to enable Macros and, in case of the agreement is received, the executable file runs the ransomware virus.

However, spam is not the only method used by hackers to spread severe computer infections. Experts from LosVirus[3] name the following techniques among less, but still actively used, ransomware distribution techniques:

  • stand-alone file installers;
  • malicious content on the web;
  • fake software updates;
  • malicious ads or interlinks.

It's important to stress the fact that many ransomware viruses are capable of evading detection. Therefore, it's not sufficient to install anti-malware program and expect that it will ensure hundred percent protection. People's responsibility is to avoid visiting illegal websites, carefully check software or its parts before downloading, and so on. In short, it's a must practice secure web browsing rules.

Make Defender virus removal an easy task

Ransomware virus is the most prominent cyber threat in 2018[4] and will probably remain in this position for quite a long time. If the files that the file-encrypting virus locks are not important, then Defender ransomware virus and the whole family of ransomware are not that severe as that can be detected and eliminated with the help of a powerful anti-malware tool quite easily.

Manual Defender ransomware removal is hardly possible unless you are an experienced IT professional. Those who want to remove Defender virus quickly and efficiently, you can use programs like FortectIntego, SpyHunter 5Combo Cleaner or Malwarebytes.

Right after Defender virus removal, you may try to decrypt files using one of the data recovery programs or other applicable data recovery methods.

do it now!
Fortect Happiness
Intego Happiness
Compatible with Microsoft Windows Compatible with macOS
What to do if failed?
If you failed to fix virus damage using Fortect Intego, submit a question to our support team and provide as much details as possible.
Fortect Intego has a free limited scanner. Fortect Intego offers more through scan when you purchase its full version. When free scanner detects issues, you can fix them using free manual repairs or you can decide to purchase the full version in order to fix them automatically.
Alternative Software
Different software has a different purpose. If you didn’t succeed in fixing corrupted files with Fortect, try running SpyHunter 5.
Alternative Software
Different software has a different purpose. If you didn’t succeed in fixing corrupted files with Intego, try running Combo Cleaner.

Getting rid of Defender virus. Follow these steps

Manual removal using Safe Mode

If .defender virus blocks your anti-virus program, then you should restart your PC into Safe Mode with Networking. The following steps will help you to do so correctly:

Important! →
Manual removal guide might be too complicated for regular computer users. It requires advanced IT knowledge to be performed correctly (if vital system files are removed or damaged, it might result in full Windows compromise), and it also might take hours to complete. Therefore, we highly advise using the automatic method provided above instead.

Step 1. Access Safe Mode with Networking

Manual malware removal should be best performed in the Safe Mode environment. 

Windows 7 / Vista / XP
  1. Click Start > Shutdown > Restart > OK.
  2. When your computer becomes active, start pressing F8 button (if that does not work, try F2, F12, Del, etc. – it all depends on your motherboard model) multiple times until you see the Advanced Boot Options window.
  3. Select Safe Mode with Networking from the list. Windows 7/XP
Windows 10 / Windows 8
  1. Right-click on Start button and select Settings.
  2. Scroll down to pick Update & Security.
    Update and security
  3. On the left side of the window, pick Recovery.
  4. Now scroll down to find Advanced Startup section.
  5. Click Restart now.
  6. Select Troubleshoot. Choose an option
  7. Go to Advanced options. Advanced options
  8. Select Startup Settings. Startup settings
  9. Press Restart.
  10. Now press 5 or click 5) Enable Safe Mode with Networking. Enable safe mode

Step 2. Shut down suspicious processes

Windows Task Manager is a useful tool that shows all the processes running in the background. If malware is running a process, you need to shut it down:

  1. Press Ctrl + Shift + Esc on your keyboard to open Windows Task Manager.
  2. Click on More details.
    Open task manager
  3. Scroll down to Background processes section, and look for anything suspicious.
  4. Right-click and select Open file location.
    Open file location
  5. Go back to the process, right-click and pick End Task.
    End task
  6. Delete the contents of the malicious folder.

Step 3. Check program Startup

  1. Press Ctrl + Shift + Esc on your keyboard to open Windows Task Manager.
  2. Go to Startup tab.
  3. Right-click on the suspicious program and pick Disable.

Step 4. Delete virus files

Malware-related files can be found in various places within your computer. Here are instructions that could help you find them:

  1. Type in Disk Cleanup in Windows search and press Enter.
    Disk cleanup
  2. Select the drive you want to clean (C: is your main drive by default and is likely to be the one that has malicious files in).
  3. Scroll through the Files to delete list and select the following:

    Temporary Internet Files
    Recycle Bin
    Temporary files

  4. Pick Clean up system files.
    Delete temp files
  5. You can also look for other malicious files hidden in the following folders (type these entries in Windows Search and press Enter):


After you are finished, reboot the PC in normal mode.

Remove Defender using System Restore

You have to remove Defender ransomware to get the chance to recover files and start using your PC normally. If you cannot do that because virus keeps blocking your antivirus, here's what you have to do:

  • Step 1: Reboot your computer to Safe Mode with Command Prompt
    Windows 7 / Vista / XP
    1. Click Start Shutdown Restart OK.
    2. When your computer becomes active, start pressing F8 multiple times until you see the Advanced Boot Options window.
    3. Select Command Prompt from the list Select 'Safe Mode with Command Prompt'

    Windows 10 / Windows 8
    1. Press the Power button at the Windows login screen. Now press and hold Shift, which is on your keyboard, and click Restart..
    2. Now select Troubleshoot Advanced options Startup Settings and finally press Restart.
    3. Once your computer becomes active, select Enable Safe Mode with Command Prompt in Startup Settings window. Select 'Enable Safe Mode with Command Prompt'
  • Step 2: Restore your system files and settings
    1. Once the Command Prompt window shows up, enter cd restore and click Enter. Enter 'cd restore' without quotes and press 'Enter'
    2. Now type rstrui.exe and press Enter again.. Enter 'rstrui.exe' without quotes and press 'Enter'
    3. When a new window shows up, click Next and select your restore point that is prior the infiltration of Defender. After doing that, click Next. When 'System Restore' window shows up, select 'Next' Select your restore point and click 'Next'
    4. Now click Yes to start system restore. Click 'Yes' and start system restore
    Once you restore your system to a previous date, download and scan your computer with FortectIntego and make sure that Defender removal is performed successfully.

Bonus: Recover your data

Guide which is presented above is supposed to help you remove Defender from your computer. To recover your encrypted files, we recommend using a detailed guide prepared by security experts.

It's not yet clear whether it's possible to recover encrypted .defender files. Therefore, you should give the following methods a try. 

If your files are encrypted by Defender, you can use several methods to restore them:

Install Data Recovery Pro

Data Recovery Pro is an application capable of recovering accidentally deleted files of files lost due to system's crash. However, it often appears useful in decryption of files damaged by ransomware. 

  • Download Data Recovery Pro;
  • Follow the steps of Data Recovery Setup and install the program on your computer;
  • Launch it and scan your computer for files encrypted by Defender ransomware;
  • Restore them.

Try Windows Previous Versions feature

This method may help to recover individual files encrypted by Defender ransomware virus. This way, you won't recover folders or groups of file, but only the most important documents. However, the feature is not available for those who haven't had a System Restore feature enabled before the attack. 

  • Find an encrypted file you need to restore and right-click on it;
  • Select “Properties” and go to “Previous versions” tab;
  • Here, check each of available copies of the file in “Folder versions”. You should select the version you want to recover and click “Restore”.

ShadowExplorer might be useful

If Defender virus does not removed Shadow Volume Copies, this method can help you to recover most of the files. There's only one way to find that out – to follow these steps:

  • Download Shadow Explorer (;
  • Follow a Shadow Explorer Setup Wizard and install this application on your computer;
  • Launch the program and go through the drop down menu on the top left corner to select the disk of your encrypted data. Check what folders are there;
  • Right-click on the folder you want to restore and select “Export”. You can also select where you want it to be stored.

Currently neither paid nor free Defender decryptor is available

Finally, you should always think about the protection of crypto-ransomwares. In order to protect your computer from Defender and other ransomwares, use a reputable anti-spyware, such as FortectIntego, SpyHunter 5Combo Cleaner or Malwarebytes

How to prevent from getting ransomware

Access your website securely from any location

When you work on the domain, site, blog, or different project that requires constant management, content creation, or coding, you may need to connect to the server and content management service more often. The best solution for creating a tighter network could be a dedicated/fixed IP address.

If you make your IP address static and set to your device, you can connect to the CMS from any location and do not create any additional issues for the server or network manager that needs to monitor connections and activities. VPN software providers like Private Internet Access can help you with such settings and offer the option to control the online reputation and manage projects easily from any part of the world.


Recover files after data-affecting malware attacks

While much of the data can be accidentally deleted due to various reasons, malware is one of the main culprits that can cause loss of pictures, documents, videos, and other important files. More serious malware infections lead to significant data loss when your documents, system files, and images get encrypted. In particular, ransomware is is a type of malware that focuses on such functions, so your files become useless without an ability to access them.

Even though there is little to no possibility to recover after file-locking threats, some applications have features for data recovery in the system. In some cases, Data Recovery Pro can also help to recover at least some portion of your data after data-locking virus infection or general cyber infection. 


About the author
Gabriel E. Hall
Gabriel E. Hall - Passionate web researcher

If this free guide helped you and you are satisfied with our service, please consider making a donation to keep this service alive. Even a smallest amount will be appreciated.

Contact Gabriel E. Hall
About the company Esolutions