QOPZ Virus (.QOPZ File) Ransomware 🔐 FIX & DECRYPT

Written by Brendan Smith

The QOPZ virus is a STOP/DJVU family of ransomware-type infections 1. This virus encrypts your files (video, photos, documents) that can be tracked by a specific “.qopz” extension. It uses a strong encryption method, which makes it impossible to calculate the key in any way.

QOPZ uses a unique key for each victim, with one exception:

  • If QOPZ cannot establish a connection to its command and control server (C&C Server) before starting the encryption process, it uses the offline key. This key is the same for all victims, making it possible to decrypt files encrypted during a ransomware attack.
Brendan Smith
Brendan Smith
IT Security Expert
First, scan your PC with antivirus tool!
I will try to help you remove QOPZ virus and will show how to decrypt or restore encrypted files. There is no better way to recognize, remove and prevent ransomware than to use an anti-malware software from GridinSoft.
Gridinsoft Anti-Malware 6-day trial available.
EULA | Privacy Policy | 10% Off Coupon
Subscribe to our Telegram channel to be the first to know about news and our exclusive materials on information security.

I have gathered a complete collection of all possible solutions, tips, and practices in neutralizing the QOPZ virus and decrypting files. In some cases, it is easy to recover your files. And sometimes it is just impossible.

There are several universal methods for recovering encrypted .qopz files, which will be demonstrated below. It is vital to read the entire instruction manual carefully and make sure to understand it all. Do not skip any steps. Each of these steps is very important and must be completed by you.

Is Qopz virus?

☝️ Qopz can be correctly identified as a STOP/DJVU ransomware-type virus.


🤔 Qopz virus is ransomware that originates from the DJVU/STOP family. Its primary purpose is to encrypt files that are important to you. After that ransomware virus asks its victims for a ransom fee ($490 – $980) in BitCoin.

The Qopz ransomware is a specific kind of malware that encrypts your files and then forces you to pay to restore them.

Qopz virus is similar to other representatives of the same DJVU family: Xash, Gash, Saba, Sato, Fofd. This virus encrypts all popular file types and adds its particular “.qopz” extension into all files. For example, the file “1.jpg”, will be changed into “1.jpg.qopz“. As soon as the encryption is accomplished, the virus drops a specific message file “_readme.txt” and adds it to all folders that contain the modified files.

The image below gives a clear vision of how the files with “.qopz” extension look like:

Qopz Virus - encrypted .qopz files

Qopz File (STOP/DJVU Ransomware)

NameQopz Virus
Ransomware family2DJVU/STOP3 ransomware
Ransomware note_readme.txt
RansomFrom $490 to $980 (in Bitcoins)
Contactsupport@fishmail.top, datarestorehelp@airmail.cc
DetectionTrojan:Win32/CryptInject.CP!MTB, Win32:Ransom-ZO [Trj], Ransom.Conticrypt
  • Encrypted most of your files (photos, videos, documents) and added a particular “.qopz” extension;
  • Can delete Volume Shadow copies to make victim’s attempts to restore data impossible;
  • Adds a list of domains to HOSTS file to block access to certain security-related sites;
  • Installs password-stealing Trojan on the system, like Vidar Stealer or RedLine Stealer;
  • Manages to install a SmokeLoader backdoor;
Fix Tool To remove possible malware infections, scan your PC:

6-day free trial available.

This _readme.txt file asking payment is for getting files back via decryption key:

_readme.txt (STOP/DJVU Ransomware)

_readme.txt (STOP/DJVU Ransomware) – The scary alert demanding from users to pay the ransom to decrypt the encoded data contains these frustrating warnings

Qopz ransomware arrives as a set of processes meant to perform different tasks on a victim’s computer. One of the first ones being launched is winupdate.exe, a tricky process that displays a fake Windows update prompt during the attack. This is meant to convince the victim that a Windows update causes a sudden system slowdown. However, at the same time, the ransomware runs another process (usually named after four random characters) which starts scanning the system for target files and encrypting them. Next, the ransomware deletes Volume Shadow Copies from the system using the following CMD command:

vssadmin.exe Delete Shadows /All /Quiet

Once deleted, it becomes impossible to restore the previous computer state using System Restore Points. The thing is, ransomware operators are getting rid of any Windows OS-based methods that could help the victim to restore files for free. In addition, the crooks modify the Windows HOSTS file by adding a list of domains and mapping them to the local IP. As a result, the victim will run into a DNS_PROBE_FINISHED_NXDOMAIN error when accessing one of the blocked websites.

We noticed that ransomware attempts to block websites that publish various how-to guides for computer users. By restricting specific domains, the crooks are trying to prevent the victim from reaching relevant and helpful ransomware-attack-related information online. The virus also saves two text files on the victim’s computer that provide attack-related details – the victim’s public encryption key and personal ID. These two files are called bowsakkdestx.txt and PersonalID.txt.

Qopz ransomware virus saves public encryption key and victim's id in bowsakkdestx.txt file

After all these modifications, the malware doesn’t stop. Variants of STOP/DJVU tend to drop Vidar password-stealing Trojans on compromised systems. This threat has a lengthy list of capabilities, such as:

  • Stealing Steam, Telegram, Skype login/password;
  • Stealing cryptocurrency wallets;
  • Downloading malware to the computer and running it;
  • Stealing browser cookies, saved passwords, browsing history, and more;
  • Viewing and manipulating files on victim’s computer;
  • Allowing the hackers to remotely perform other tasks on the victim’s computer.

The cryptography algorithm used by DJVU/STOP ransomware family is AES-256. So, if your files got encrypted with an online decryption key, which is totally unique, the sad reality is that it is impossible to decrypt the files without a unique key.

In case Qopz worked in online mode, it is impossible for you to gain access to the AES-256 key. It is stored on a distant server owned by the criminals who distribute the Qopz virus.

For receiving the decryption key, the payment should be $980. To obtain the payment details, the victims are encouraged by the message to contact the frauds by email (support@fishmail.top).

The message by the ransomware states the following information:


Don't worry, you can return all your files!

All your files like photos, databases, documents and other important are encrypted with strongest encryption and unique key.
The only method of recovering files is to purchase decrypt tool and unique key for you.
This software will decrypt all your encrypted files.

What guarantees you have?

You can send one of your encrypted file from your PC and we decrypt it for free.
But we can decrypt only 1 file for free. File must not contain valuable information.

You can get and look video overview decrypt tool:


Price of private key and decrypt software is $980.
Discount 50% available if you contact us first 72 hours, that's price for you is $490.

Please note that you'll never restore your data without payment.

Check your e-mail "Spam" or "Junk" folder if you don't get answer more than 6 hours.

To get this software you need write on our e-mail:


Reserve e-mail address to contact us:


Your personal ID:

Do not pay for Qopz!

Please, try to use the available backups, or Decrypter tool

_readme.txt file also indicates that the computer owners must contact the Qopz representatives within 72 hours starting when files were encrypted. On the condition of getting in touch within 72 hours, users will be granted a 50% rebate. Thus the ransom amount will be minimized to $490). However, stay away from paying the ransom!

I advise you not to contact these crooks and do not pay. One of the most real working solutions to recover lost data – just using the available backups or use Decrypter tool.

The peculiarity of all such viruses apply similar actions for generating the unique decryption key to recover the ciphered data.

Thus, unless the ransomware is still in the stage of development or possesses some hard-to-track flaws, manually recovering the ciphered data is a thing you can’t perform. The only solution to prevent the loss of your valuable data is to make backups of your crucial files regularly.

Note that even if you do maintain such backups regularly, they ought to be put into a specific location without loitering not being connected to your main workstation.

The backup may be kept on the USB flash drive or some alternative external hard drive storage. Optionally, you may refer to the help of online (cloud) information storage.

Needless to mention, when you maintain your backup data on your common device, it may be similarly ciphered as well as other data.

For this reason, locating the backup on your main device is surely not a good idea.

How I was infected?

Ransomware has various methods to build into your system. But it doesn’t matter what method was used in your case.

Qopz virus attack

Qopz ransomware attack following a successful phishing attempt.

Nevertheless, these are the common leaks through which it may be injected into your PC:

  • hidden installation along with other apps, especially the utilities that work as freeware or shareware;
  • dubious link in spam emails leading to the virus installer
  • online free hosting resources;
  • using illegal peer-to-peer (P2P) resources for downloading pirated software.

There were cases when the Qopz virus was disguised as some legitimate tool, for example, in the messages demanding to initiate some unwanted software or browser updates. This is typically the way how some online frauds aim to force you into installing the Qopz ransomware manually by actually making you directly participate in this process.

Surely, the bogus update alert will not indicate that you are going to inject the ransomware. This installation will be concealed under some alert mentioning that you allegedly should update Adobe Flash Player or some other dubious program.

The cracked apps represent the damage too. Using P2P is both illegal and may result in the injection of serious malware, including the Qopz ransomware.

To sum up, what can you do to avoid injecting the Qopz ransomware into your device? Even though there is no 100% guarantee to prevent your PC from getting damaged, there are certain tips I want to give you to prevent Qopz penetration. You must be cautious while installing free software today.

Make sure you always read what the installers offer in addition to the main free program. Stay away from opening dubious email attachments. Do not open files from unknown addresses. Of course, your current security program must always be updated.

The malware does not speak openly about itself. It will not be mentioned in the list of your available programs. However, it will be masked under some malicious process running regularly in the background, starting from the moment when you launch your PC.

How To Remove Qopz Virus?

In addition to encoding a victim’s files, the Qopz infection has also started to install the Vidar Stealer on PC to steal account credentials, cryptocurrency wallets, desktop files, and more.4
Reasons why I would recommend GridinSoft5

There is no better way to recognize, remove and prevent ransomware than to use anti-malware software from GridinSoft6.

  1. Download Removal Tool.

    You can download GridinSoft Anti-Malware by clicking the button below:

  2. Run the setup file.

    When setup file has finished downloading, double-click on the setup-antimalware-fix.exe file to install GridinSoft Anti-Malware on your system.

    Run Setup.exe

    An User Account Control asking you about allowing GridinSoft Anti-Malware to make changes to your device. So, you should click “Yes” to continue with the installation.

    GridinSoft Anti-Malware Setup

  3. Press “Install” button.

    GridinSoft Anti-Malware Install

  4. Once installed, Anti-Malware will automatically run.

    GridinSoft Anti-Malware Splash-Screen

  5. Wait for complete.

    GridinSoft Anti-Malware will automatically scan your system for Qopz infections and other malicious programs. This process can take 20-30 minutes, so I suggest you periodically check on the status of the scan process.

    GridinSoft Anti-Malware Scanning for Qopz virus

  6. Click on “Clean Now”.

    When the scan has finished, you will see the infection list that GridinSoft Anti-Malware detected. To remove them click on the “Clean Now” button in the right corner.

    Qopz virus Scan Result
  7. Trojan Killer for special instances

    In certain instances, Qopz ransomware can block the running of setup files of different anti-malware programs. In this situation, you need to utilize the removable drive with a pre-installed antivirus tool.

    There is a really little number of security tools that are able to be set up on USB drives, and antiviruses that can do so in most cases require to obtain quite an expensive license. For this instance, I can recommend you to use another solution of GridinSoft – Trojan Killer Portable. It has a 14-day cost-free trial mode that offers the entire features of the paid version 7. This term will definitely be 100% enough to wipe malware out.

How To Decrypt .qopz Files?

Restore solution for big “.qopz files

Try removing .qopz extension on a few BIG files and opening them. Either the Qopz virus read and did not encrypt the file, or it bugged and did not add the filemarker. If your files are very large (2GB+), the latter is most likely. Please, let me know in the comments if that will work for you.

The newest extensions released around the end of August 2019 after the criminals made changes. This includes Foty, Foza, Vypt, etc.

As a result of the changes made by the criminals, STOPDecrypter is no longer supported. It has been removed and replaced with the Emsisoft Decryptor for STOP Djvu Ransomware developed by Emsisoft.

You can download free decryption tool here: Decryptor for STOP Djvu.

  1. Download and run the decryption tool.

    Start downloading the decryption tool.

    Make sure to launch the decryption utility as an administrator. You need to agree with the license terms that will come up. For this purpose, click on the “Yes” button:

    Emsisoft Decryptor - license terms

    As soon as you accept the license terms, the main decryptor user interface comes up:

    Emsisoft Decryptor - user interface

  2. Select folders for decryption.

    Based on the default settings, the decryptor will automatically populate the available locations to decrypt the currently available drives (the connected ones), including the network drives. Extra (optional) locations can be selected with the help of the “Add” button.

    Decryptors normally suggest several options considering the specific malware family. The current possible options are presented in the Options tab and can be activated or deactivated there. You may locate a detailed list of the currently active Options below.

  3. Click on the “Decrypt” button.

    As soon as you add all the desired locations for decryption to the list, click on the “Decrypt” button to initiate the decryption procedure.

    Note that the main screen may turn you to a status view, letting you know of the active process and the decryption statistics of your data:

    Emsisoft Decryptor - the decryption statistics

    The decryptor will notify you as soon as the decryption procedure is completed. If you need the report for your personal papers, you can save it by choosing the “Save log” button. Note that it is also possible to copy it directly to your clipboard and paste it into emails or messages here if you need to do so.

The Emsisoft Decryptor might display different messages after a failed attempt to restore your quiz files:

✓ Error: Unable to decrypt file with ID: [your ID]
No corresponding decryption key exists in the Emsisoft decryptor’s database.
✓ No key for New Variant online ID: [your ID]
Notice: this ID appears to be an online ID. Decryption is impossible
Your original files were encrypted with an online key. So no one else has the same encryption/decryption key pair. Recovery of qopz files without paying the criminals is impossible. 🙁
✓ Result: No key for new variant offline ID: [example ID]
This ID appears be an offline ID. Decryption may be possible in the future.
An offline key was used, but files could not be restored (the offline decryption key isn’t available yet). But, receiving this message is good news for you because it might be possible to restore your qopz files in the future. 🙂
It can take a few weeks or months until the decryption key gets found and uploaded to the decryptor. Please follow updates regarding the decryptable DJVU versions here.
✓ Remote name could not be resolved
It’s an indication of a DNS issue on your PC. Our first recommendation is to reset your HOSTS file back to default.

How to Restore .qopz Files?

In some case Qopz ransomware is not doom for your files…

Qopz ransomware encryption mechanism feature is next: it encrypts every file byte-by-byte, then saves a file copy, deleting (and not overriding!) the original file. Hence, the information on the file location on the physical disk is lost, but the original file is not deleted from the physical disk. The cell, or the sector where this file was stored, can still contain this file, but the file system does not list it and can be overwritten by data that has been loaded to this disk after the deletion. Hence, it is possible to recover your files using special software.

I recently had my pc infected by the Qopz virus. It managed to bypass 2 Antivirus software and two malware fighters.

Anyway, after realizing it was an online algorithm, it is impossible to retrieve my encrypted files. I also had my backup drive plugged in at the time of the virus, and this was also infected, or so I thought. Every folder within my backup drive had been infected and was encrypted. However, despite losing some important files, I retrieved almost 80% of my 2TB storage.

When I started going through the folders, I noticed the readme.txt ransom note in every folder. I opened some of the folders and found that all files that were not in a subfolder within that folder had been encrypted. However, I found a flaw and glimmer of hope when I went into the subfolders in other folders and found that these files had not been encrypted. Every folder within my c and d drives, including subfolders, had been encrypted, but this was not the case with the backup drive. Having subfolders created within a folder has saved 80% of my data.

As I said, I believe this to be only a small loophole on a backup drive. I’ve since found a further 10 % of my data on another hard drive on a different pc. So my advice is if you use a backup drive, create subfolders. I was lucky, I guess. But I was also unlucky that the virus hit as I was transferring some files from my backup.

Hopefully, this can help some other people in my situation.

Jamie Newland
Some pointers for recovery repair of Qopz files (true for all STOP/DJVU variants):

  • I have seen Qopz variants fail to encrypt deeper nested folders, so that you can check that. You may find those are not encrypted.
  • This ransomware saves encrypted data to a new file, and deletes the original. So there’s a slight chance part of that deleted file can be recovered using file recovery software. It’s unlikely the folder structure can be restored, so a free tool like PhotoRec may be as good as any.
  • This ransomware only partially encrypts (about the first 150 KB), so the not encrypted part may be recoverable depending on file size and type of data.
  • Joep

    Recovering your files with PhotoRec

    PhotoRec is an open-source program created for file recovery from damaged disks or file recovery in case they are deleted. However, as time has gone by, this program got the ability to recover the files of 400 different extensions. Hence, it can be used for data recovery after the ransomware attack

    At first, you need to download this app. It is 100% free, but the developer states there is no guarantee that your files will be recovered. PhotoRec is distributed in a pack with other utilities of the same developer – TestDisk. The downloaded archive will have a TestDisk name but don’t worry. PhotoRec files are right inside.

    To open PhotoRec, you need to find and open “qphotorec_win.exe” file. No installation is required – this program has all the files it needs inside of the archive, hence, you can fit it on your USB drive and try to help your friend/parents/anyone who was attacked by DJVU/STOP ransomware.

    PhotoRec file in the folder

    After the launch, you will see the screen showing you the full list of your disk spaces. However, this information is likely useless because the required menu is placed a bit higher. Click this bar, then choose the disk which was attacked by ransomware.

    Choose the disc in PhotoRec

    After choosing the disk, you need to choose the destination folder for the recovered files. This menu is located at the lower part of the PhotoRec window. The best decision is to export them on a USB drive or any other type of removable disk.

    Choosing the destination folder of recovery

    Then, you need to specify the file formats. This option is located at the bottom, too. As it was mentioned, PhotoRec can recover files of about 400 different formats.

    Choose the file format

    Finally, you can start files recovery by pressing the “Search” button. You will see the screen where the results of the scan and recovery are shown.

    Recovery process

    Qopz files recovery guide

    Frequently Asked Questions

    How my computer got hacked and my files encrypted by ransomware?

    Djvu ransomware is often spread via email attachments or links and on websites that offer pirated or cracked software or services. Unfortunately, users are often tricked into downloading and executing the ransomware on their computers, which ultimately leads to the encryption of their data.

    How to Restore Access to “.qopz” Files After a Ransomware Attack

    If you find that your files have been encrypted due to a ransomware attack, your access to them may be limited. To restore access, you will need to decrypt them. However, keep in mind that Djvu ransomware typically uses an online key to encrypt files, making them only decryptable by attackers.

    Is It Possible to Decrypt “.qopz” Files for Free?

    While it may be possible to recover data encrypted by Djvu ransomware utilizing Emsisoft’s Djvu decryption software, it is essential to note that offline keys are rarely utilized. Therefore, there is no guarantee that your files will be decrypted for free.

    Why You Should Not Pay Ransom to Cybercriminals

    Paying a ransom is not recommended, as it would financially support cybercriminals, and there is no assurance of receiving the necessary decryption software. Instead, you can consider utilizing legitimate decryption tools and services or seek assistance from cybersecurity professionals.

    How to Remove Ransomware and Protect Your Computer

    Although security software like Gridinsoft can detect and remove active ransomware infections on your computer, it is only the initial step in the recovery process from a ransomware attack. It is crucial to implement proactive security measures, such as keeping software up-to-date, using strong passwords, and backing up your data regularly, to prevent future attacks.

    Video Guide

    It’s my favorite video tutorial: How to use GridinSoft Anti-Malware and Emsisoft Decryptor to fix ransomware infections.

    If the guide doesn’t help you to remove Qopz virus, please download the GridinSoft Anti-Malware that I recommended. Do not forget to share your experience in solving the problem. Please leave a comment here! This can help other victims to understand they are not alone. And together, we will find ways to deal with this issue.

    I need your help to share this article.

    It is your turn to help other people. I have written this article to help people like you. You can use the buttons below to share this on your favorite social media Facebook, Twitter, or Reddit.
    Brendan Smith
    QOPZ Ransomware — How To Restore & Decrypt Files?

    Name: QOPZ Virus

    Description: QOPZ Virus is a STOP/DJVU family of ransomware-type infections. This virus encrypts your files, video, photos, documents that can be tracked by a specific qopz extension. So, you can't use them at all after that QOPZ ransomware asks victims for a ransom fee ($490 - $980) in Bitcoin.

    Operating System: Windows

    Application Category: Virus

    User Review
    4.21 (14 votes)
    Comments Rating 0 (0 reviews)


    1. STOP/DJVU Ransomware: https://gridinsoft.com/ransomware/djvu
    2. My files are encrypted by ransomware. What should I do now?
    3. About DJVU (STOP) Ransomware.
    4. Windows passwords vulnerability (Mimikatz HackTool): https://howtofix.guide/mimikatz-hacktool/
    5. GridinSoft Anti-Malware Review from HowToFix site: https://howtofix.guide/gridinsoft-anti-malware/
    6. More information about GridinSoft products: https://gridinsoft.com/comparison
    7. Trojan Killer Review: https://howtofix.guide/trojan-killer/

    German Japanese Spanish Portuguese (Brazil) French Turkish Chinese (Traditional) Korean Indonesian Hindi Italian

    About the author

    Brendan Smith

    I'm Brendan Smith, a passionate journalist, researcher, and web content developer. With a keen interest in computer technology and security, I specialize in delivering high-quality content that educates and empowers readers in navigating the digital landscape.

    With a focus on computer technology and security, I am committed to sharing my knowledge and insights to help individuals and organizations protect themselves in the digital age. My expertise in cybersecurity principles, data privacy, and best practices allows me to provide practical tips and advice that readers can implement to enhance their online security.

    Leave a Reply