Kostya ransomware / virus (Virus Removal Guide) - Oct 2016 update

Manual removal using Safe Mode

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 10 / Windows 8

1. Right-click on Start button and select Settings.
   
   
2. Scroll down to pick Update & 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.
7. Go to Advanced options.
8. Select Startup Settings.
9. Press Restart.
10. Now press 5 or click 5) Enable Safe Mode with Networking.

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.
   
3. Scroll down to Background processes section, and look for anything suspicious.
4. Right-click and select Open file location.
   
5. Go back to the process, right-click and pick 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.
   
   
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
   Downloads
   Recycle Bin
   Temporary files

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

   %AppData%
   %LocalAppData%
   %ProgramData%
   %WinDir%

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

Remove Kostya using System Restore

• 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
  
  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.
• Step 2: Restore your system files and settings
  1. Once the Command Prompt window shows up, enter cd restore and click Enter.
  2. Now type rstrui.exe and press Enter again..
  3. When a new window shows up, click Next and select your restore point that is prior the infiltration of Kostya. After doing that, click Next.
  4. Now click Yes to start system restore.
  Once you restore your system to a previous date, download and scan your computer with FortectIntego and make sure that Kostya removal is performed successfully.

Bonus: Recover your data

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

Data Recovery Pro recovery method

As we have already mentioned in our article, Kostya virus decryption can be bypassed using data recovery software, such as Data Recovery Pro. Though there is not guarantee for a 100% success, you may still try out this method if you are desperate to get your files back.

• 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 Kostya ransomware;
• Restore them.

Windows Previous Versions feature recovery method

This method is quite a successful data recovery technique, when it comes to ransomware-encrypted files. Unfortunately, it is not universal and can be used only on some individual files but not the whole computer. Besides, System Restore function is necessary to make it work. If it has been enabled before Kostya infiltration, please follow these steps: 

• 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 recovery method

The final method we would like to introduce again involves using data recovery software. This time, ShadowExplorer. Run this software to recover your files from the Volume Shadow Copies if they haven’t been deleted by the virus yet. To learn how to get this program running, follow the guidelines here:

• Download Shadow Explorer (http://shadowexplorer.com/);
• 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.