FileSlack Ransomware

Also Known As: FileSlack ransomware
Distribution: Low
Damage level: Severe

FileSlack ransomware removal instructions

What is FileSlack?

Discovered by Michael Gillespie, The FileSlack program is categorized as ransomware. Like most ransomware-type computer infections, FileSlack is used by cyber criminals who attempt to encrypt users' data (stored on computers) and make ransom demands. Once installed, FileSlack renames all encrypted files by adding the ".FileSlack" extension (e.g. "1.jpg" becomes "1.jpg.FileSlack") and generates a ransom message within the "Readme_Restore_Files.txt" text file.

The "Readme_Restore_Files.txt" text file informs FileSlack victims that all files are encrypted and warns them not to try modify them in any way. To restore them, users are encouraged to contact the developers via the or email addresses. FileSlack's developers provide no other details, however, it is likely that they will send them when they are contacted via one of the email addresses. Most cyber criminals demand a ransom payment in cryptocurrency (usually Bitcoin). They also make promises to send a decryption tool once they receive payment. Cyber criminals offer free decryption of one or several files as 'proof' that they have a tool capable of file decryption. Most ransomware developers use cryptography algorithms (symmetric or asymmetric) that generate unique keys. Therefore, when files are encrypted, they can be decrypted only with a specific tool available from the cyber criminals. Other 'decryptors' simply do not work due to the complexities of the cryptography algorithms. There is no information regarding other tools that might be capable of FileSlack data decryption. Therefore, victims with computers infected with this ransomware are encouraged to contact the developers. Despite this, most criminals who develop programs of this type provide no decryption tools, even if their ransom demands are met. The only free way method is to use a data backup and restore everything from there.

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

FileSlack decrypt instructions

Most ransomware-type infections are designed to serve the same purpose: to encrypt data and make ransom demands. Frend, _Write_To_Emails_ and Cryptotes are just some examples of other malicious programs similar to FileSlack. Typically, the main differences are cryptography algorithm used for encryption and cost of decryption tool (or key). Unfortunately, most cyber criminals design ransomware infections to be 'uncrackable' and only they can provide the correct decryption tool. They can be cracked only in some rare cases when these malicious programs are not fully developed or have bugs/flaws. In any case, maintain regular backups and to store them on remote servers or unplugged storage devices. If not, data backups are encrypted together with other files stored on the PC's hard drive.

How did ransomware infect my computer?

It is not known exactly how developers proliferate FileSlack, however, these programs are generally distributed using spam (email) campaigns, Trojans, various (untrustworthy) third party software download sources, software cracking tools, and fake software updaters. Spam campaigns are used as tools to deliver malicious attachments (or web links) by sending emails, however, these attachments download and install malware only if they are opened. Some examples of commonly used attachments are Microsoft Office documents, PDF files, archive files (such as ZIP, RAR), executable files, and so on. Trojans are also categorized as malicious programs. These cause chain infections - when installed, they proliferate other malicious programs such as ransomware. Untrustworthy software download channels such as freeware download websites, free file hosting sites, third party downloaders/installers, P2P (Peer-to-Peer) networks, eMule, torrent clients etc., are often used to present malicious files as legitimate. When downloaded and executed, they install malware. Software cracking tools often deliver the reverse outcome: rather than activating software (allowing users to bypass paid activation), they install malicious programs. Fake software updaters usually infect systems by exploiting bugs/flaws of outdated software or by downloading and installing malware rather than the expected/promised software updates.

Threat Summary:
NameFileSlack ransomware
Threat TypeRansomware, Crypto Virus, Files locker
SymptomsCan'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 methodsInfected email attachments (macros), torrent websites, malicious ads.
DamageAll 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.

To eliminate FileSlack ransomware our malware researchers recommend scanning your computer with Spyhunter.
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Free scanner checks if your computer is infected. To remove malware, you have to purchase the full version of Spyhunter.

How to protect yourself from ransomware infections?

A few simple rules can be useful to avoid computer infection with ransomware or other high-risk infections. Received emails that contain attachments and are sent from unknown/suspicious addresses should be handled with care. Do not open these attachments or links without making sure that it is safe to do so. Generally, these emails may seem legitimate and important, however, they are usually irrelevant to their recipients. Avoid downloading (or installing) software using third party downloaders or installers, unofficial websites, and so on. Download software using official websites and direct links. Keep software updated but use tools provided by official software developers only. Note that using software cracking tools is a cyber crime. Furthermore, these tools often cause computer infections rather than activating any software or operating systems. Finally, have reputable anti-virus/anti-spyware software installed and enabled at all times. If your computer is already infected with FileSlack, we recommend running a scan with Spyhunter for Windows to automatically eliminate this ransomware.

Text presented in FileSlack ransomware text file :

All your files are encrypted
Do not try modify files
My email,

Screenshot of files encrypted by FileSlack (".FileSlack" extension):

Files encrypted by FileSlack

FileSlack ransomware removal:

Instant automatic removal of FileSlack ransomware: Manual threat removal might be a lengthy and complicated process that requires advanced computer skills. Spyhunter is a professional automatic malware removal tool that is recommended to get rid of FileSlack ransomware. Download it by clicking the button below:
▼ DOWNLOAD Spyhunter By 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 Spyhunter.

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 FileSlack 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 FileSlack 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 FileSlack 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 FileSlack 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 FileSlack, 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 FileSlack 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 FileSlack ransomware:

About the author:

Tomas Meskauskas

Tomas Meskauskas - expert security researcher, professional malware analyst.

I am passionate about computer security and technology. I have an experience of over 10 years working in various companies related to computer technical issue solving and Internet security. I have been working as an author and editor for since 2010. Follow me on Twitter and LinkedIn to stay informed about the latest online security threats. Contact Tomas Meskauskas.

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Malware activity

Global virus and spyware activity level today:

Medium threat activity

Increased attack rate of infections detected within the last 24 hours.

QR Code
FileSlack ransomware QR code
A QR code (Quick Response Code) is a machine-readable code which stores URLs and other information. This code can be read using a camera on a smartphone or a tablet. Scan this QR code to have an easy access removal guide of FileSlack ransomware on your mobile device.
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Platform: Windows

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