The sole aim of LISP ransomware is to take victim’s important files hostage, and convince one to pay a ransom for data recovery tools. As explained in the ransom note _readme.txt, the criminals behind this crime state that documents, photos, videos and databases were encrypted with strongest encryption, and the only way to decrypt them is to purchase a decryption key and software from the criminals. In this guide, I will explain how to remove LISP conputer virus and restore your files step-by-step. The attackers demand paying a ransom to them, and the price of it ranges based on how quickly the victim writes to them and pays the required sum of money. If the victim contacts the criminals and pays within 3 full days (72 hours) the ransom price equals to $490. If the victim delays the payment, the price doubles to $980. Just like any other criminals, people behind this STOP/DJVU variant demands to purchase a corresponding sum of money in certain cryptocurrency (such as Bitcoin) and transfer it to their crypto-wallet. This helps to guarantee their privacy when cashing out the money. The ransom note explains that the victim should write to one of provided emails – either helpmanager@mail.ch or restoremanager@airmail.cc and include one encrypted file for test decryption. The attackers promise to provide decrypted .lisp file variant in their reply email. This technique is used to convince the victim to pay the ransom. However, do not get fooled – it does not mean that the criminals will provide the decryption tools after receiving your money, nor that it will work on all of your files. Finally, it is never worth funding cybercrime industry this way, not to mention the fact that the criminals will target you as a potential “payer” in future attacks. That said, we recommend you to remove LISP ransomware virus first and then take actions to restore your files.

What the ransomware developers did to your files

Ransomware is extremely popular cyber extortion tool nowadays, as it allows to virtually harass a computer user by making one’s files inaccessible. For this to happen, the criminals create a malicious software that leverages cryptographic algorithms such as RSA to encrypt files with public key, and save the decryption key (the private one) to criminals’ servers. However, we must stress out the fact that STOP/DJVU ransomware variants, such as LISP virus, have slightly different modus operandi than other crypto-viruses such as DHARMA. The first thing that this specific virus does after entering the system is try to contact its Command & Control servers. If it manages to establish the connection, it obtains an “online” encryption key, or, in other words, generates unique encryption/decryption key pair for the victim. If the ransomware fails to establish the connection, it uses a hardcoded encryption key, therefore called the “offline” one, to encrypt victim’s data. You can learn more about online and offline encryption methods, and chances to decrypt .lisp files either way, below this article or in this lengthy guide.

Get to know crypto-malware distribution techniques to avoid getting infected

LISP ransomware virus is distributed via traditional ransomware proliferation paths, such as malicious email spam, illegal downloads and fake websites serving malicious payloads. To begin with, we will describe the method that is the most common for all STOP/DJVU malware variants. The developers of this specific ransomware variant tend to create a malicious executable that is presented as a crack or keygen tool for the victim. Computer users infected by previous variants of DJVU claim they have downloaded the virus in a form of a fake Adobe Photoshop crack, video editing programs’ keygens, or game cracks. All of them have searched for these tools on illegal file sharing domains that suggest getting these copyright-protected materials in a form of torrents that can be downloaded via agents like zMule or uTorrent. Unfortunately, after opening such malicious file, thinking that it will help to activate paid software for free, the victim discovers that it was a disguised malware. That is why we always recommend purchasing legitimate software versions and enjoying full set of program’s features without having to worry about your security and privacy. Another popular way to insert malware into victims’ computers is to distribute email spam. The attackers compose email messages that try to urge the victim to open the attached document (Word, PDF or another) to view its contents. Unfortunately, nowadays documents can be used to transmit malware of various kinds, such as Trojans or ransomware. That is why we recommend to avoid opening any links or attachments in emails you DID NOT expect to receive. Cybercriminals can even spoof the sender’s email address to make the message seem more convincing, so beware of that.

Remove LISP ransomware virus completely

In order to secure your privacy, file system and other sensitive information such as your login credentials, we recommend you to initiate LISP ransomware removal as soon as possible. For this matter, we recommend using an automated virus removal software of your choice. You can find instructions on how to remove LISP ransomware virus yourself right below this article. Do not forget to follow each step attentively, and change all of your browser-saved passwords afterward. To restore your Windows OS components and repair general virus damage to the computer, scan with SYSTEM MECHANIC ULTIMATE DEFENSE . OUR GEEKS RECOMMEND Our team recommends a two-step rescue plan to remove ransomware and other remaining malware from your computer, plus repair caused virus damage to the system: GeeksAdvice.com editors select recommended products based on their effectiveness. We may earn a commission from affiliate links, at no additional cost to you. Learn more. Get INTEGO ANTIVIRUS for Windows to remove ransomware, Trojans, adware and other spyware and malware variants and protect your PC and network drives 24/7. This VB100-certified security software uses state-of-art technology to provide protection against ransomware, Zero-Day attacks and advanced threats, Intego Web Shield blocks dangerous websites, phishing attacks, malicious downloads and installation of potentially unwanted programs. Use INTEGO Antivirus to remove detected threats from your computer. Read full review here. RESTORO provides a free scan that helps to identify hardware, security and stability issues and presents a comprehensive report which can help you to locate and fix detected issues manually. It is a great PC repair software to use after you remove malware with professional antivirus. The full version of software will fix detected issues and repair virus damage caused to your Windows OS files automatically. RESTORO uses AVIRA scanning engine to detect existing spyware and malware. If any are found, the software will eliminate them. Read full review here.

Method 1. Enter Safe Mode with Networking

Before you try to remove LISP ransomware virus virus, you must start your computer in Safe Mode with Networking. Below, we provide the easiest ways to boot PC in the said mode, but you can find additional ones in this in-depth tutorial on our website – How to Start Windows in Safe Mode. Also, if you prefer a video version of the tutorial, check our guide How to Start Windows in Safe Mode on Youtube. Instructions for Windows XP/Vista/7 users Instructions for Windows 8/8.1/10/11 users Now, you can search for and remove LISP ransomware virus files. It is very hard to identify files and registry keys that belong to the ransomware virus, Besides, malware creators tend to rename and change them repeatedly. Therefore, the easiest way to uninstall such type of a computer virus is to use a reliable security program such as INTEGO Antivirus. For virus damage repair, consider using RESTORO.

Method 2. Use System Restore

In order to use System Restore, you must have a system restore point, created either manually or automatically. Instructions for Windows XP/Vista/7 users Instructions for Windows 8/8.1/10/11 users After restoring the system, we recommend scanning the system with antivirus or anti-malware software. In most cases, there won’t be any malware remains, but it never hurts to double-check. In addition, we highly recommend checking ransomware prevention guidelines provided by our experts in order to protect your PC against similar viruses in the future.

Alternative software recommendations

Malwarebytes Anti-Malware Removing spyware and malware is one step towards cybersecurity. To protect yourself against ever-evolving threats, we strongly recommend purchasing a Premium version of Malwarebytes Anti-Malware, which provides security based on artificial intelligence and machine learning. Includes ransomware protection. See pricing options and protect yourself now.

System Mechanic Ultimate Defense If you’re looking for an all-in-one system maintenance suite that has 7 core components providing powerful real-time protection, on-demand malware removal, system optimization, data recovery, password manager, online privacy protection and secure driver wiping technology. Therefore, due to its wide-range of capabilities, System Mechanic Ultimate Defense deserves Geek’s Advice approval. Get it now for 50% off. You may also be interested in its full review.

Disclaimer. This site includes affiliate links. We may earn a small commission by recommending certain products, at no additional cost for you. We only choose quality software and services to recommend.

Decrypt LISP files

Fix and open large LISP files easily:

It is reported that STOP/DJVU ransomware versions encrypt only the beginning 150 KB of each file to ensure that the virus manages to affect all files on the system. In some cases, the malicious program might skip some files at all. That said, we recommend testing this method on several big (>1GB) files first.

STOP/DJVU decryption tool usage guide

STOP/DJVU ransomware versions are grouped into old and new variants. LISP ransomware virus is considered the new STOP/DJVU variant, just like BPTO, ISWR, ISZA, BPSM, ZOUU, MBTF, ZNSM (find full list here). This means full data decryption is now possible only if you have been affected by offline encryption key. To decrypt your files, you will have to download Emsisoft Decryptor for STOP DJVU, a tool created and maintained by a genius security researcher Michael Gillespie. Note! Please do not spam the security researcher with questions whether he can recover your files encrypted with online key - it is not possible. In order to test the tool and see if it can decrypt LISP files, follow the given tutorial.

Meanings of decryptor’s messages

The LISP decryption tool might display several different messages after failed attempt to restore your files. You might receive one of the following messages: Error: Unable to decrypt file with ID: [example ID] This message typically means that there is no corresponding decryption key in the decryptor’s database. No key for New Variant online ID: [example ID]Notice: this ID appears to be an online ID, decryption is impossible This message informs that your files were encrypted with online key, meaning no one else has the same encryption/decryption key pair, therefore data recovery without paying the criminals is impossible. Result: No key for new variant offline ID: [example ID]This ID appears to be an offline ID. Decryption may be possible in the future. If you were informed that an offline key was used, but files could not be restored, it means that the offline decryption key isn’t available yet. However, receiving this message is extremely good news, meaning that it might be possible to restore your LISP extension files in the future. It can take a few months until the decryption key gets found and uploaded to the decryptor. We recommend you to follow updates regarding the decryptable DJVU versions here. We strongly recommend backing up your encrypted data and waiting.

Victims of LISP ransomware virus should report the Internet crime incident to the official government fraud and scam website according to their country:

In the United States, go to the On Guard Online website.In Australia, go to the SCAMwatch website.In Germany, go to the Bundesamt für Sicherheit in der Informationstechnik website.In Ireland, go to the An Garda Síochána website.In New Zealand, go to the Consumer Affairs Scams website.In the United Kingdom, go to the Action Fraud website.In Canada, go to the Canadian Anti-Fraud Centre.In India, go to Indian National Cybercrime Reporting Portal.In France, go to the Agence nationale de la sécurité des systèmes d’information.

If you can’t find an authority corresponding to your location on this list, we recommend using any search engine to look up “[your country name] report cyber crime”. This should lead you to the right authority website. We also recommend staying away from third-party crime report services that are often paid. It costs nothing to report Internet crime to official authorities. Another recommendation is to contact your country’s or region’s federal police or communications authority.