Remove Koti Ransomware (.koti File Recovery)

A widely spread and one of the notorious crypto-virus to date is called STOP or DJVU. It has a large family with more than two hundred variants that has infected, and continuously contaminating computers as of this moment. Actually, there is new addition to this family and it is called Koti ransomware. Like older versions, Koti is taking advantage of mass mailing campaign to distribute copies of the ransomware to random recipients.

The infection of Koti ransomware starts when the recipient runs the email attachment. So far, it is hard for ordinary computer users to detect that the correspondence they have received is spam email. Attackers cleverly tailored it to appear as document originating from prominent organization or reputable institution. When it arrives on the inbox, recipient only sees a trustworthy sender, name, subject, and attached document file. Thinking that the email is legitimate and because of its encouraging subject and contents, recipient often persuade to open the attachment without knowing that this will kick-off the Koti ransomware attack.

Once run, Koti ransomware starts to drop a number of files on the computer. Some of it are stored and system folders and can run as system processes that regularly initiates the malicious code on Windows boot-up sequence. Then, Koti ransomware will search the local hard drive for target files that are commonly regular data like documents, spreadsheets, images, photos, music files, videos, databases, archives, and more. Koti ransomware uses a sophisticated technique in encrypting these data and appends .koti file extension to mark them as infected and probably to disassociate them from default programs.

Koti Ransomware

Koti ransomware developers are always ready to negotiate with victims and to show that they are willing to help with file recovery, a ransom note is generated on the same folder as .koti encrypted files. As stated, victims are required to pay $980 as compensation for the decryption tool and private key.

There may have no other way to fully recover all .koti encrypted files as of this moment, but paying the attackers does not secure that purpose either. Keep in mind that dealing with cyber crooks does not always end up in the favour of victims. Paying the ransom demand do not guarantee that attackers are going to send the tool or if it will be able to decrypt all Koti files from the infected computer.

How to Remove Koti Ransomware

Ransomware files are placed deeply into the system and on various locations, thus, thorough scanning is vital to totally remove Koti virus. Aside from our suggested tool, you may also run your own security program.

Though affected files may be impossible to decrypt due to complexity of the encryption, you can still try recovery method like alternative tool, Shadow Explorer or Previous Version as described below.

Stage 1: Scan the Computer with Anti-Malware Tool

1. Download free anti-malware scanner called MalwareBytes Anti-Malware.
Malwarebytes Anti-Malware Download Link (this will open a new window)

2. After downloading, install the program. It may run automatically or you have to double-click on the downloaded file MBSetup.exe.

3. Carry out the installation with default setup process.

4. After the installation process, click the Get Started button to launch the program.

5. Continue with the prompts until the main program opens.

6. On the main console, click on Scan to run most complete detection method to find hidden objects associated to Koti ransomware.

7. Scanning may take a while. Please wait until the anti-malware tool is done with the checking.

MBAM-threatscan

8. Once the scan has completed, the tool will display the list of detected threats. Remove all identified malicious items and restart the computer if necessary.

Stage 2: Double-check for Koti’s leftover with Microsoft’s Malicious Software Removal Tool

1. Download the free scanner called Malicious Software Removal Tool.
Malicious Software Removal Tool Download Link (this will open a new window)

download-msrt

2. The tool automatically checks the operating system and suggest appropriate download version. Click on Download button to begin. Save the file to a convenient location, preferably on Desktop.

3. After downloading the file, Windows will prompt that download has completed. Click Run to start scanning for Koti ransomware. Another option is to browse the location folder and double click on the file to run.

MSRT Icon

4. The tool will display Welcome screen, click Next. Please note the message “This tool is not a replacement for an antivirus product.” You must understand that this program is made specifically to find and remove malware, viruses, Trojans, and other harmful elements on the computer. It was not designed to protect the computer.

msrt1

5. Next, you will see Scan Type. Please choose Full Scan to ensure that all Koti ransom virus entities and other harmful files left on the computer will be found and removed. For advanced computer user, you can opt for Customized Scan, if there are other drives or folders you wanted to include in this scan.

msrt2

6. Full scan may take a while, please wait for Malicious Software Removal Tool to complete the tasks. However, you may cancel the scan anytime by clicking on the Cancel button.

msrt3

7. After scanning, the tool will reveal all identified threats. There may be other threats that our first scan fails to detect. Please remove/delete all detected items.

8. When removal procedure is complete, you may now close Malicious Software Removal Tool. We hope that Koti ransomware have been completely deleted from the computer. Please restart Windows to proceed with the normal operation.

Stage 3 : Unlocking files with Koti Decryption Tool

Emsisoft Decryptor for STOP Djvu will work only if affected files were encrypted using Offline Keys. Koti ransomware uses the alternate Offline Keys during encryption if there is a problem encountered while communicating to a remote command-and-control server. Follow the guide to start recovering .koti encrypted files.

1. As precautionary measures, we suggest to BACKUP all your .koti encrypted files first on a separate media (USB Drive, Flash Drive, DVD Discs, etc…).

2. Download Emsisoft Decryptor for STOP Djvu from this archive page.

3. Right-click on decrypt_STOPDjvu.exe and click “Run as Administrator“. Windows may prompt “Do you want to allow this app…” just click Yes to continue.

4. By default, the tool will pre-populate the locations where encrypted files were identified. To include other directories, simply click Add Folder button.

5. To start recovering files infected by Koti ransomware, click on Decrypt button to start the procedure. The interface will display status of the current decryption process.

decrypt_STOPDjvu.exe

We will update this section once the full decryption tool is on hand. In the meantime, please try other options below if the above procedure is not not effective.

Option 1: Windows Previous Version Tool

Windows Vista and Windows 7 have a feature called Previous Versions. However, this tool is only usable if restore point was made prior to Koti ransomware infection. To use this tool and recover files affected by the virus, please follow these steps:

1. Open My Computer or Windows Explorer.

2. Right-click on the affected files or folders. From the drop-down list, please click on Restore previous versions.

3. New window will open display all backup copy of files and folders you wanted to recover. Choose the appropriate file and click on Open, Copy, or Restore. Restoring selected files overwrites the current encrypted files on the computer.

Option 2: Use ShadowExplorer to restore files encrypted by Koti Ransomware

Just like Previous Version tool, ShadowExplorer is taking advantage of shadow copy created by Windows. This tool allows you to retrieve older version of files before it was encrypted by Koti ransomware.

1. Download ShadowExplorer from the official web site.

2. Install the program with the default settings.

3. The program should run automatically after installation. If not, double-click on ShadowExplorer icon.

4. You can see the drop-down list on top of the console. Please select proper drive and the most recent point-in-time shadow copies of files you wish to restore prior to Koti ransomware infection.

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5. Right-click on the Drive, Folder, or File you wish to restore and click Export…

6. Lastly, ShadowExplorer will prompt for location where you want to save the copy of recovered files.

Post Last Modified On May 18, 2020

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