Nols ransomware removal instructions
What is Nols?
Belonging to the Djvu ransomware family, Nols is malicious software designed to encrypt data and demand ransom payments for decryption (i.e., purchase of a decryption tool and unique key). During the encryption process, all files are renamed with the ".nols" extension. Therefore, "1.jpg" becomes "1.jpg.nols" and so on for all affected files. After this process is complete, Nols creates a text file ("_readme.txt"), which it stores in all folders.
The ransom message within the "_readme.txt" file states that the victim's data has been encrypted, and to recover files, decryption software and a unique key (generated individually for each victim) is required. These tools can be purchased from the developers of Nols. To prove their ability to restore data, the cyber criminals offer to decrypt one file free of charge. They will do so, as long as the file does not contain 'valuable information' (likely implying that it cannot be a database, backup, large excel sheet, or similar). The size of ransom is 980 USD, however, the message states that if users contact the criminals within 72 hours, the cost is reduced by fifty percent. There are email addresses provided and victims are informed that if they do not receive a response within six hours, they should check their "Spam/Junk" folders. The message also claims that, without purchasing these tools, users will not be able to recover their data. Unfortunately, this is often accurate. Ransomware programs use strong encryptions, which cannot be "cracked" by any free decryption software. In most cases, only the software that encrypted the data is capable of decoding it. Despite this, do not communicate with cyber criminals or meet their ransom demands. In most cases of ransomware infections, victims receive no decryption tools even if they pay. Their data remains permanently damaged. The only solution is to restore the encrypted files from a backup, if one was made before the infection and stored separately.
Screenshot of a message encouraging users to pay a ransom to decrypt their compromised data:
All ransomware shares many similarities. For example, Werd, Uta, PAY IT OR LOST IT, and OmniSphere are akin to Nols. Malicious programs of this type encrypt data and demand ransoms to be paid. They differ by the cryptographic algorithm used (symmetric or asymmetric) and size of ransom. Cyber criminals prefer digital currencies (e.g. cryptocurrencies, pre-paid vouchers, etc.), as these transactions are difficult/impossible to trace. Manual decryption (without the involvement of ransomware developers) is impossible, unless the software is still in development and/or has flaws/bugs. To ensure data safety from data encryption and damaging attacks, keep backups on unplugged storage devices and/or remote servers. Ideally, multiple copies should be stored in different locations.
How did ransomware infect my computer?
|Threat Type||Ransomware, Crypto Virus, Files locker.|
|Detection Names||Avast (FileRepMalware), BitDefender (Trojan.GenericKD.41924862), ESET-NOD32 (A Variant Of Win32/Kryptik.GXMI), Kaspersky (Trojan-Downloader.Win32.Upatre.iehr), Full List (VirusTotal)|
|Encrypted Files Extension||.nols|
|Ransom Demanding Message||_readme.txt text file|
|Cyber Criminal Contactfirstname.lastname@example.org, email@example.com|
|Symptoms||Cannot open files stored on your computer, previously functional files now have a different extension (for example, my.docx.locked). A ransom demand message is displayed on your desktop. Cyber criminals demand payment of a ransom (usually in bitcoins) to unlock your files.|
|Additional Information||This malware is designed to show a fake Windows Update window and modify the Windows "hosts" file to prevent users from accessing cyber security websites (more information below).|
|Distribution methods||Infected email attachments (macros), torrent websites, malicious ads, unofficial activation and updating tools.|
|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.|
|Malware Removal (Windows)||
To eliminate possible malware infections, scan your computer with legitimate antivirus software. Our security researchers recommend using Malwarebytes.
How to protect yourself from ransomware infections
Irrelevant and/or suspicious emails, especially those received from unknown senders (addresses) should not be opened or read. Do not open attachments found in these emails, since doing so, will result in an infection. Only official and verified download sources should be used. Peer-to-Peer sharing networks (BitTorrent, eMule, Gnutella, etc.), unofficial and free file-hosting websites, third party downloaders, and similar are untrustworthy and should not be used. Software should be activated using legal means, and not via "cracking" tools. These are also classed as high-risk. The same extends to software updating. Programs and apps should updated using functions/tools provided by genuine developers. Have reputable anti-virus/anti-spyware software installed and kept up-to-date. These programs should be used to perform regular system scans and for the removal of detected threats. If your computer is already infected with Nols, we recommend running a scan with Malwarebytes for Windows to automatically eliminate this ransomware.
Text presented in Nols ransomware text file ("_readme.txt"):
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:
Screenshot of files encrypted by Nols (".nols" extension):
Screenshot of fake Windows update pop-up displayed during the encryption:
IMPORTANT NOTE! - As well as encrypting data, ransomware-type infections from the Djvu malware family also add a number of entries to the Windows "hosts" file. The entries contain URLs of various websites, most of which are related to malware removal. This is done to prevent users from accessing malware security websites and seeking help. Our website (PCrisk.com) is also on the list. Removing these entries, however, is simple - you can find detailed instructions in this article (note that, although the steps are shown in the Windows 10 environment, the process is virtually identical on all versions of the Microsoft Windows operating system).
Screenshot of websites added to Windows hosts file:
There are currently two versions of Djvu ransomware infections: old and new. The old versions were designed to encrypt data by using a hard-coded "offline key" whenever the infected machine had no internet connection or the server was timing out/not responding. Therefore, some victims were able to decrypt data using a tool developed by cyber security researcher, Michael Gillespie, however, since the encryption mechanism has been slightly changed (hence the new version, released in August, 2019), the decrypter no longer works and is no longer supported. If your data has been encrypted by an older version, you might be able to restore it with the another tool developed by Emsisoft and Michael Gillespie. It supports a total of 148 Djvu variants and you can find more information, as well as download link and decryption instructions in Emsisoft's official web page.
Screenshot of Djvu decryption tool by Emsisoft and Michael Gillespie:
Additionally, Emsisoft is now providing a service that allows you to decrypt data (again, only if it was encrypted by Djvu variants released before August, 2019) for those victims who have copies of files before and after encryption. Victims simply upload the pairs of original and encrypted file to Emsisoft's Djvu decryption web page and download the aforementioned decryption tool (the download link will be provided after uploading files). Note that file processing may take some time, so be patient. Note also that the system must have a reliable internet connection during the entire decryption process, otherwise it will fail.
Screenshot of Emsisoft's Djvu decryption service web page:
Nols ransomware removal:
Instant automatic malware removal:
Manual threat removal might be a lengthy and complicated process that requires advanced computer skills. Malwarebytes is a professional automatic malware removal tool that is recommended to get rid of malware. Download it by clicking the button below:
- What is Nols?
- STEP 1. Nols virus removal using safe mode with networking.
- STEP 2. Nols ransomware removal using System Restore.
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.
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.
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.
Video showing how to start Windows 10 in "Safe Mode with Networking":
Log in to the account infected with the Nols 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.
2. When Command Prompt mode loads, enter the following line: cd restore and press ENTER.
3. Next, type this line: rstrui.exe and press ENTER.
4. In the opened window, click "Next".
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 Nols ransomware virus infiltrating your PC).
6. In the opened window, click "Yes".
7. After restoring your computer to a previous date, download and scan your PC with recommended malware removal software to eliminate any remaining Nols 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 Nols 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.
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 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 Nols 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, and Desktop folders.
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:
Malwarebytes Anti-Ransomware Beta uses advanced proactive technology that monitors ransomware activity and terminates it immediately - before reaching users' files:
- 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 Nols ransomware: