Gamma Ransomware

Gamma ransomware removal instructions

What is Gamma?

Gamma is a ransomware-type virus discovered by Jakub Kroustek and designed to stealthily infiltrate systems and encrypt data. The virus is a part of the Crysis ransomware family. During encryption, Gamma ransomware adds the “.gamma” extension to every affected file. For example, it changes “1.jpg” to “[].gamma“. It also displays a ransom-demand message in a pop-up type window and creates a text file called “FILES ENCRYPTED.txt“, placing it in each folder that contains encrypted files.

The “FILES ENCRYPTED” text file contains a short message stating that all data has been locked, and if users want to recover their encrypted files, they must contact cyber criminals using one of the email addresses provided. There is no detailed information regarding the encryption algorithm (symmetric or asymmetric) used, however, successful decryption requires a unique key generated individually for each victim. Keys are stored on a remote server controlled by cyber criminals. The ransom required is also unknown – Gamma ransomware developers state that the cost depends on how quickly they are contacted via the email addresses. It does state that the ransom must be paid in Bitcoins. They also offer a “free trial” for decryption of one unarchived file no larger that 1MB. Nevertheless, cyber criminals should not be trusted, since most ignore victims and do not provide decrypted files as promised, even when the ransom is paid. Therefore, ignore all requests to pay ransoms. Unfortunately, there are currently no tools capable of cracking Gamma encryption and restoring data free of charge. The only solution is to restore everything from a backup.

Screenshot of a message encouraging users to pay a ransom to decrypt their compromised data:

Gamma decrypt instructions

There are many ransomware-type viruses (such as StorageCryptSAVEfilesScarab-Hitler, etc.) that are developed by different cyber criminals. They serve an identical purpose – to encrypt data and demand ransom payments. These viruses differ in terms of cost of decryption (required ransom cost) and encryption algorithm used. Generally, the RSA and AES algorithms (and some others) are used to encrypt data. Therefore restoring data manually without contacting ransomware developers is impossible unless the ransomware-type virus contains bugs or is still in development. Therefore, maintain regular data backups. Store them on a remote server (such as Cloud) or unplugged storage device, otherwise the malware encrypts backups together with regular data.

How did ransomware infect my computer?

Systems are infected with ransomware-type viruses in a number of ways. Typically they infiltrate through third party downloaders (that present malware as legitimate software), trojans (viruses that cause other virus infections), emails/spam (malicious attachments that, once opened, cause system infections), fake software updaters (that download and install malware rather than updating outdated software or fixing bugs), and so on.

Threat Summary:
Name Gamma virus
Threat Type Ransomware, Crypto Virus, Files locker
Symptoms Can’t open files stored on your computer, previously functional files now have a different extension, for example my.docx.locked. A ransom demanding message is displayed on your desktop. Cyber criminals are asking to pay a ransom (usually in bitcoins) to unlock your files.
Distribution methods Infected email attachments (macros), torrent websites, malicious ads.
Damage All files are encrypted and cannot be opened without paying a ransom. Additional password stealing trojans and malware infections can be installed together with a ransomware infection.
Removal To eliminate Gamma virus our malware researchers recommend scanning your computer with Restoro.
▼ Download Restoro
Free scanner checks if your computer is infected. To remove malware, you have to purchase the full version of Restoro.

How to protect yourself from ransomware infections?

To prevent computers infections (including those by ransomware-type viruses), browse the web and install, download/update software with caution. Avoid opening emails from unknown senders, especially if they contain attachments. Download software using official and trustworthy websites only. Do not use third party installers/downloaders, since they often include bundled software and rogue applications. Keep your operating system and installed software updated and your antivirus software enabled at all times. If your computer is already infected with Gamma, we recommend running a scan with Restoro for Windows to automatically eliminate this ransomware.

Text presented in Gamma ransomware pop-up window:

All your files have been encrypted!
All your files have been encrypted due to a security problem with your PC. If you want to restore them, write us to the e-mail
Write this ID in the title of your message 1E857D00
In case of no answer in 24 hours write us to theese
You have to pay for decryption in Bitcoins. The price depends on how fast you write to us. After payment we will send you the decryption tool that will decrypt all your files. 
Free decryption as guarantee
Before paying you can send us up to 1 file for free decryption. The total size of files must be less than 1Mb (non archived), and files should not contain valuable information. (databases,backups, large excel sheets, etc.) 
How to obtain Bitcoins
The easiest way to buy bitcoins is LocalBitcoins site. You have to register, click ‘Buy bitcoins’, and select the seller by payment method and price. 
Also you can find other places to buy Bitcoins and beginners guide here: 
Do not rename encrypted files. 
Do not try to decrypt your data using third party software, it may cause permanent data loss. 
Decryption of your files with the help of third parties may cause increased price (they add their fee to our) or you can become a victim of a scam.

Screenshot of Gamma’s text file (“FILES ENCRYPTED.txt“):

Gamma text file

Text presented within this file:

all your data has been locked us
You want to return?
write email or

Screenshot of files encrypted by Gamma (“.gamma” extension):

Files encrypted by Gamma

Gamma ransomware removal:

Instant automatic removal of Gamma virus:Manual threat removal might be a lengthy and complicated process that requires advanced computer skills. Restoro is a professional automatic malware removal tool that is recommended to get rid of Gamma virus. Download it by clicking the button below:
▼ DOWNLOAD RestoroBy downloading any software listed on this website you agree to our Privacy Policy and Terms of Use. Free scanner checks if your computer is infected. To remove malware, you have to purchase the full version of Restoro.

Quick menu:

Step 1

Windows XP and Windows 7 users: Start your computer in Safe Mode. Click Start, click Shut Down, click Restart, click OK. During your computer start process, press the F8 key on your keyboard multiple times until you see the Windows Advanced Option menu, and then select Safe Mode with Networking from the list.

Safe Mode with Networking

Video showing how to start Windows 7 in “Safe Mode with Networking”:

Windows 8 users: Start Windows 8 is Safe Mode with Networking – Go to Windows 8 Start Screen, type Advanced, in the search results select Settings. Click Advanced startup options, in the opened “General PC Settings” window, select Advanced startup. Click the “Restart now” button. Your computer will now restart into the “Advanced Startup options menu”. Click the “Troubleshoot” button, and then click the “Advanced options” button. In the advanced option screen, click “Startup settings”. Click the “Restart” button. Your PC will restart into the Startup Settings screen. Press F5 to boot in Safe Mode with Networking.

Windows 8 Safe Mode with networking

Video showing how to start Windows 8 in “Safe Mode with Networking”:

Windows 10 users: Click the Windows logo and select the Power icon. In the opened menu click “Restart” while holding “Shift” button on your keyboard. In the “choose an option” window click on the “Troubleshoot”, next select “Advanced options”. In the advanced options menu select “Startup Settings” and click on the “Restart” button. In the following window you should click the “F5” button on your keyboard. This will restart your operating system in safe mode with networking.

windows 10 safe mode with networking

Video showing how to start Windows 10 in “Safe Mode with Networking”:

Step 2

Log in to the account infected with the Gamma virus. Start your Internet browser and download a legitimate anti-spyware program. Update the anti-spyware software and start a full system scan. Remove all entries detected.

If you cannot start your computer in Safe Mode with Networking, try performing a System Restore.

Video showing how to remove ransomware virus using “Safe Mode with Command Prompt” and “System Restore”:

1. During your computer start process, press the F8 key on your keyboard multiple times until the Windows Advanced Options menu appears, and then select Safe Mode with Command Prompt from the list and press ENTER.

Boot your computer in Safe Mode with Command Prompt

2. When Command Prompt mode loads, enter the following line: cd restore and press ENTER.

system restore using command prompt type cd restore

3. Next, type this line: rstrui.exe and press ENTER.

system restore using command prompt rstrui.exe

4. In the opened window, click “Next”.

restore system files and settings

5. Select one of the available Restore Points and click “Next” (this will restore your computer system to an earlier time and date, prior to the Gamma ransomware virus infiltrating your PC).

select a restore point

6. In the opened window, click “Yes”.

run system restore

7. After restoring your computer to a previous date, download and scan your PC with recommended malware removal software to eliminate any remaining Gamma ransomware files.

To restore individual files encrypted by this ransomware, try using Windows Previous Versions feature. This method is only effective if the System Restore function was enabled on an infected operating system. Note that some variants of Gamma are known to remove Shadow Volume Copies of the files, so this method may not work on all computers.

To restore a file, right-click over it, go into Properties, and select the Previous Versions tab. If the relevant file has a Restore Point, select it and click the “Restore” button.

Restoring files encrypted by CryptoDefense

If you cannot start your computer in Safe Mode with Networking (or with Command Prompt), boot your computer using a rescue disk. Some variants of ransomware disable Safe Mode making its removal complicated. For this step, you require access to another computer.

To regain control of the files encrypted by Gamma, you can also try using a program called Shadow Explorer. More information on how to use this program is available here.

shadow explorer screenshot

To protect your computer from file encryption ransomware such as this, use reputable antivirus and anti-spyware programs. As an extra protection method, you can use programs called HitmanPro.Alert and EasySync CryptoMonitor, which artificially implant group policy objects into the registry to block rogue programs such as Gamma ransomware.

Note that Windows 10 Fall Creators Update includes a “Controlled Folder Access” feature that blocks ransomware attempts to encrypt your files. By default, this feature automatically protects files stored in the Documents, Pictures, Videos, Music, Favorites as well as Desktop folders.

Controll Folder Access

Windows 10 users should install this update to protect their data from ransomware attacks. Here is more information on how to get this update and add an additional protection layer from ransomware infections.

HitmanPro.Alert CryptoGuard – detects encryption of files and neutralises any attempts without need for user-intervention:

hitmanproalert ransomware prevention application

Malwarebytes Anti-Ransomware Beta uses advanced proactive technology that monitors ransomware activity and terminates it immediately – before reaching users’ files:

malwarebytes anti-ransomware

  • The best way to avoid damage from ransomware infections is to maintain regular up-to-date backups. More information on online backup solutions and data recovery software Here.

Other tools known to remove Gamma ransomware:

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.