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How to Open .js Files ( Javascript Hidden Virus)

how-to-open-do-not-open-js-files-sensorstechforum-comSince many of the users on our forum and on our complaint e-mails have reported to be victims of infections caused by .js files(JavaScript source code file format) we have decided to serve the need of knowledge our readers should have and educate them how to protect themselves from malicious execution of a JavaScript that may render their files equal to garbage and make them pay a hefty sum. Bear in mind, we will provide the best advices on our abilities, but even the best advise won’t protect you if you do not pay attention to what you are doing while browsing on a daily basis. Let us begin!

The E-mail

This segment is the most important piece of education you will ever receive if you are a beginner, because it will briefly teach you how to spot the difference between fake e-mail messages and actual e-mails. This is also due to the fact that the most often cause of infection by .js files viruses is via e-mail attachments. So when we are talking about .js files protection, we are also addressing spam e-mail protection as well.

The first step when receiving an e-mail and deciding whether or not to open a .js file in it is to have a system. Such system is very simple to memorize. If I could summarize it, I would definitely use this sentence:

“Start from the top!”

The “top” is the subject of the e-mail that is sent to you and the source e-mail it is sent from. Here you can sort out the cheap e-mails which you can immediately delete even without having to open them. These are the so-called “promotion” and “important” e-mails that are not from organizations, but different individuals that you have never met before. Usually, people tend to write e-mail topics of something familiar to the user who they are sending the message to. Otherwise, why would have provided your e-mail address to specific people for contact, right?


But then again, what if the message does not have a subject or what if it is sent by a company, like Amazon, for example (see the picture below). And what if the e-mail is saying that your PayPal account is suspended? The counter reaction to this in case you are not sure is to use a secure environment when opening the e-mail.Also, bear in mind of the obvious, and this is if a .js file is portrayed to you as a document in an e-mail, it may not be, because it is highly untypical for documents to be in JavaScript.


One solution is to use a sandbox application that “wraps” your web browser or e-mail client (Mozilla Thunderbird, Microsoft Outlook) in a secure encryption on which if the ransomware infection malware is activated, may immediately shut down because it will be stopped inside the program. One very good example for a sandbox application is a neat little app, called Sandboxie which we tested below. It even has the option to auto wrap every program you start in a sandbox automatically without affecting the performance of your computer even the slightest.


However, some sophisticated viruses and malware who run on .js to infect users may be coded and obfuscated with expensive obfuscators and exploit kits that may even go as far as through the sandbox application itself. Here is where you will need an advanced protection tool against these programs when you do your e-mailing – an advanced anti-malware tool is just the thing for you. Unlike traditional antivirus programs, most anti-malware programs are more frequently updated, and they are not just focused on .js malware, but on other suspicious files roaming around in spam e-mails carrying what may just be the lasts Locky or Cerber viruses.

There are a variety of anti-malware programs to choose from out there, and many would argue that the more well-known a security software is, the more it becomes a target for malware, because of the higher interest in it. This is why there should be a balance between a tool on which the hackers have little intelligence while at the same time is frequently maintained and updated. The best choice is a tool that will have a second-generation heuristic update system. This means that if the latest Locky hits in the U.S., the program on your computer should know about this and have the heuristics as fast as possible after this “zero patient” type of infection. One good example for such tool is Heimdal’s professional version, which we have kindly reviewed for you below and in case you do not seem to be fond of it it there are many other tools out there amongst which you can choose.


What If I Don’t Have the Time or Experience To Check Every E-mail?

In case the situation is that dire, or you are going to be educating someone who is systematically becoming infected via e-mail and via JavaScript and other types of files, do not worry. Explaining the situation to the inexperienced user may not be successful even if you repeat It over and over again. This is why we have a brilliant idea which can help protect your daily e-mailing if you are running a Windows OS and this is to use a virtual Android OS straight on your Windows device. Craftily, right?

The idea for this unexpectedly smart solution is that most spam e-mails are designed to trick Windows users into becoming infecting with malware. Surely, there is a lot of malware written for Android, but provided a little education and malware writers prefer malicious URLs via fake advertisements or suspicious apps to infect Android users, not e-mail. More to it than that, Android devices can also be additionally secured from .js files infection with an antivirus software and other utilities and app monitors, which is great. One app that is the leader and is very simple to use (install and start) is called Nox App Player, and after using it, we felt convinced in its stability as well as security


What about Malicious URLs?

Malicious URLs are a very sophisticated method of infection and very effective as well. This is why if the proper script is written to counter your defenses, neither of the tools above may save you. Here is where we talk about direct protection against any form of malicious JavaScript files. To secure your computer, this way, especially if you are using a browser instead of an e-mail client is to educate yourself in scanning URLs manually before opening. I know, it looks complicated at the start, but bear in mind that it can be significantly simplified with free browser add-ons, like VTzilla, VirusTotal.com’s web browser add-on. Need I remind you that VIrusTotal is most likely the one of the largest (if not, the largest) web database for malware and it not only uses the combination of a wide database of malicious .js files being detected 24/7 but it also learns to detect any URL’s and malicious JavaScripts before you even opened them. All it takes to right click on the URL before opening and scan it.

What If the Inevitable Happens?

If you are using any of those beginner tools, regularly updating your operating system, etc. and still manage to become infected somehow with a .js files attack, good data management is crucial to your survival from the devastation. Below, you may find more information on how to safely store your important files and protect them from .js files viruses.


Since a lot of malware including ransomware, now may not only slither other viruses on your computer if it becomes its victim, but it may also spread worms or make the computer a part of a botnet (bot network). This makes all of the other computers connected to the same network endangered, and they may not have such defensive tools. This is why, before all, your first deal of business is to disconnect the computer from the internet “the hardware way”. This will prevent any malicious packets to travel on your LAN and infect the other devices in it. From there, you can begin coping with the situation.

Ventsislav Krastev

Ventsislav is a cybersecurity expert at SensorsTechForum since 2015. He has been researching, covering, helping victims with the latest malware infections plus testing and reviewing software and the newest tech developments. Having graduated Marketing as well, Ventsislav also has passion for learning new shifts and innovations in cybersecurity that become game changers. After studying Value Chain Management, Network Administration and Computer Administration of System Applications, he found his true calling within the cybersecrurity industry and is a strong believer in the education of every user towards online safety and security.

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About the .js Files Research

The content we publish on SensorsTechForum.com, this .js Files how-to removal guide included, is the outcome of extensive research, hard work and our team’s devotion to help you remove the specific, adware-related problem, and restore your browser and computer system.

How did we conduct the research on .js Files?

Please note that our research is based on independent investigation. We are in contact with independent security researchers, thanks to which we receive daily updates on the latest malware, adware, and browser hijacker definitions.
Furthermore, the research behind the .js Files threat is backed with VirusTotal https://www.virustotal.com/gui/home/upload.
To better understand this online threat, please refer to the following articles which provide knowledgeable details.


1.Browser Redirect – What Is It?
2.Adware Is Malicious, and It Uses Advanced Techniques to Infect
3.The Thin Red Line Between Potentially Unwanted Programs and Malware
4.The Pay-Per-Install Affiliate Business – Making Millions out of Adware
5.Malicious Firefox Extensions Installed by 455,000 Users Blocked Updates

How to Remove .js Files from Windows.

Step 1: Boot Your PC In Safe Mode to isolate and remove .js Files


Manual Removal Usually Takes Time and You Risk Damaging Your Files If Not Careful!
We Recommend To Scan Your PC with SpyHunter

Keep in mind, that SpyHunter’s scanner is only for malware detection. If SpyHunter detects malware on your PC, you will need to purchase SpyHunter's malware removal tool to remove the malware threats. Read our SpyHunter 5 review. Click on the corresponding links to check SpyHunter's EULA, Privacy Policy and Threat Assessment Criteria

1. Hold Windows key + R

2. The "Run" Window will appear. In it, type "msconfig" and click OK.

3. Go to the "Boot" tab. There select "Safe Boot" and then click "Apply" and "OK".
Tip: Make sure to reverse those changes by unticking Safe Boot after that, because your system will always boot in Safe Boot from now on.

4. When prompted, click on "Restart" to go into Safe Mode.

5. You can recognise Safe Mode by the words written on the corners of your screen.

Step 2: Uninstall .js Files and related software from Windows

Here is a method in few easy steps that should be able to uninstall most programs. No matter if you are using Windows 10, 8, 7, Vista or XP, those steps will get the job done. Dragging the program or its folder to the recycle bin can be a very bad decision. If you do that, bits and pieces of the program are left behind, and that can lead to unstable work of your PC, errors with the file type associations and other unpleasant activities. The proper way to get a program off your computer is to Uninstall it. To do that:

1. Hold the Windows Logo Button and "R" on your keyboard. A Pop-up window will appear.

2. In the field type in "appwiz.cpl" and press ENTER.

3. This will open a window with all the programs installed on the PC. Select the program that you want to remove, and press "Uninstall"
Follow the instructions above and you will successfully uninstall most programs.

Step 3: Clean any registries, created by .js Files on your computer.

The usually targeted registries of Windows machines are the following:

  • HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
  • HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
  • HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
  • HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce

You can access them by opening the Windows registry editor and deleting any values, created by .js Files there. This can happen by following the steps underneath:

1. Open the Run Window again, type "regedit" and click OK.

2. When you open it, you can freely navigate to the Run and RunOnce keys, whose locations are shown above.

3. You can remove the value of the virus by right-clicking on it and removing it.

Tip: To find a virus-created value, you can right-click on it and click "Modify" to see which file it is set to run. If this is the virus file location, remove the value.

Before starting "Step 4", please boot back into Normal mode, in case you are currently in Safe Mode.
This will enable you to install and use SpyHunter 5 successfully.

Step 4: Scan for .js Files with SpyHunter Anti-Malware Tool

1. Click on the "Download" button to proceed to SpyHunter's download page.

It is recommended to run a scan before purchasing the full version of the software to make sure that the current version of the malware can be detected by SpyHunter. Click on the corresponding links to check SpyHunter's EULA, Privacy Policy and Threat Assessment Criteria.

2. After you have installed SpyHunter, wait for it to update automatically.


3. After the update process has finished, click on the 'Malware/PC Scan' tab. A new window will appear. Click on 'Start Scan'.


4. After SpyHunter has finished scanning your PC for any files of the associated threat and found them, you can try to get them removed automatically and permanently by clicking on the 'Next' button.


If any threats have been removed, it is highly recommended to restart your PC.

Video Removal Guide for .js Files (Windows).

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Get rid of .js Files from Mac OS X.

Step 1: Uninstall .js Files and remove related files and objects

Manual Removal Usually Takes Time and You Risk Damaging Your Files If Not Careful!
We Recommend To Scan Your Mac with SpyHunter for Mac
Keep in mind, that SpyHunter for Mac needs to purchased to remove the malware threats. Click on the corresponding links to check SpyHunter’s EULA and Privacy Policy

1.Hit the ⇧+⌘+U keys to open Utilities. Another way is to click on “Go” and then click “Utilities”, like the image below shows:

2. Find Activity Monitor and double-click it:

3.In the Activity Monitor look for any suspicious processes, belonging or related to .js Files:

Tip: To quit a process completely, choose the “Force Quit” option.

4.Click on the "Go" button again, but this time select Applications. Another way is with the ⇧+⌘+A buttons.

5.In the Applications menu, look for any suspicious app or an app with a name, similar or identical to .js Files. If you find it, right-click on the app and select “Move to Trash”.

6: Select Accounts, after which click on the Login Items preference.

Your Mac will then show you a list of items that start automatically when you log in. Look for any suspicious apps identical or similar to .js Files. Check the app you want to stop from running automatically and then select on the Minus (“-“) icon to hide it.

7: Remove any left-over files that might be related to this threat manually by following the sub-steps below:

  • Go to Finder.
  • In the search bar type the name of the app that you want to remove.
  • Above the search bar change the two drop down menus to “System Files” and “Are Included” so that you can see all of the files associated with the application you want to remove. Bear in mind that some of the files may not be related to the app so be very careful which files you delete.
  • If all of the files are related, hold the ⌘+A buttons to select them and then drive them to “Trash”.

In case you cannot remove .js Files via Step 1 above:

In case you cannot find the virus files and objects in your Applications or other places we have shown above, you can manually look for them in the Libraries of your Mac. But before doing this, please read the disclaimer below:

Disclaimer! If you are about to tamper with Library files on Mac, be sure to know the name of the virus file, because if you delete the wrong file, it may cause irreversible damage to your MacOS. Continue on your own responsibility!

1: Click on "Go" and Then "Go to Folder" as shown underneath:

2: Type in "/Library/LauchAgents/" and click Ok:

3: Delete all of the virus files that have similar or the same name as .js Files. If you believe there is no such file, do not delete anything.

You can repeat the same procedure with the following other Library directories:

→ ~/Library/LaunchAgents

Tip: ~ is there on purpose, because it leads to more LaunchAgents.

Step 2: Scan for and remove .js Files files from your Mac

When you are facing problems on your Mac as a result of unwanted scripts and programs such as .js Files, the recommended way of eliminating the threat is by using an anti-malware program. SpyHunter for Mac offers advanced security features along with other modules that will improve your Mac’s security and protect it in the future.

Click the button below below to download SpyHunter for Mac and scan for .js Files:


SpyHunter for Mac

Video Removal Guide for .js Files (Mac)

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Remove .js Files from Google Chrome.

Step 1: Start Google Chrome and open the drop menu

Step 2:Move the cursor over "Tools" and then from the extended menu choose "Extensions"

Step 3: From the opened "Extensions" menu locate the unwanted extension and click on its "Remove" button.

Step 4: After the extension is removed, restart Google Chrome by closing it from the red "X" button at the top right corner and start it again.

Windows Mac OS X Google Chrome Mozilla Firefox Microsoft Edge Safari Internet Explorer Stop Push Pop-ups

Erase .js Files from Mozilla Firefox.

Step 1: Start Mozilla Firefox. Open the menu window

Step 2: Select the "Add-ons" icon from the menu.

Step 3: Select the unwanted extension and click "Remove"

Step 4: After the extension is removed, restart Mozilla Firefox by closing it from the red "X" button at the top right corner and start it again.

Windows Mac OS X Google Chrome Mozilla Firefox Microsoft Edge Safari Internet Explorer Stop Push Pop-ups

Uninstall .js Files from Microsoft Edge.

Step 1: Start Edge browser.

Step 2: Open the drop menu by clicking on the icon at the top right corner.

Step 3: From the drop menu select "Extensions".

Step 4: Choose the suspected malicious extension you want to remove and then click on the gear icon.

Step 5: Remove the malicious extension by scrolling down and then clicking on Uninstall.

Windows Mac OS X Google Chrome Mozilla Firefox Microsoft Edge Safari Internet Explorer Stop Push Pop-ups

Remove .js Files from Safari.

Step 1: Start the Safari app.

Step 2: After hovering your mouse cursor to the top of the screen, click on the Safari text to open its drop down menu.

Step 3: From the menu, click on "Preferences".

stf-safari preferences

Step 4: After that, select the 'Extensions' Tab.


Step 5: Click once on the extension you want to remove.

Step 6: Click 'Uninstall'.

stf-safari uninstall

A pop-up window will appear asking for confirmation to uninstall the extension. Select 'Uninstall' again, and the .js Files will be removed.

How to Reset Safari
IMPORTANT: Before resetting Safari make sure you back up all your saved passwords within the browser in case you forget them.

Start Safari and then click on the gear leaver icon.

Click the Reset Safari button and you will reset the browser.

Windows Mac OS X Google Chrome Mozilla Firefox Microsoft Edge Safari Internet Explorer Stop Push Pop-ups

Eliminate .js Files from Internet Explorer.

Step 1: Start Internet Explorer.

Step 2: Click on the gear icon labeled 'Tools' to open the drop menu and select 'Manage Add-ons'

Step 3: In the 'Manage Add-ons' window.

Step 4: Select the extension you want to remove and then click 'Disable'. A pop-up window will appear to inform you that you are about to disable the selected extension, and some more add-ons might be disabled as well. Leave all the boxes checked, and click 'Disable'.

Step 5: After the unwanted extension has been removed, restart Internet Explorer by closing it from the red 'X' button located at the top right corner and start it again.

Remove Push Notifications caused by .js Files from Your Browsers.

Turn Off Push Notifications from Google Chrome

To disable any Push Notices from Google Chrome browser, please follow the steps below:

Step 1: Go to Settings in Chrome.


Step 2: In Settings, select “Advanced Settings”:

advanced settings

Step 3: Click “Content Settings”:

Content Settings

Step 4: Open “Notifications”:


Step 5: Click the three dots and choose Block, Edit or Remove options:

Block, Edit or Remove

Remove Push Notifications on Firefox

Step 1: Go to Firefox Options.


Step 2: Go to “Settings”, type “notifications” in the search bar and click "Settings":


Step 3: Click “Remove” on any site you wish notifications gone and click “Save Changes”

remove push notifications firefox

Stop Push Notifications on Opera

Step 1: In Opera, press ALT+P to go to Settings.


Step 2: In Setting search, type “Content” to go to Content Settings.

content settings

Step 3: Open Notifications:


Step 4: Do the same as you did with Google Chrome (explained below):

three dots

Eliminate Push Notifications on Safari

Step 1: Open Safari Preferences.


Step 2: Choose the domain from where you like push pop-ups gone and change to "Deny" from "Allow".

.js Files FAQ

What is .js Files?

The .js Files threat is adware or browser redirect virus. It may slow your computer down siginficantly and display advertisements. The main idea is for your information to likely get stolen or more ads to appear on your device.

The creators of such unwanted apps work with pay-per-click schemes to get your computer to visit risky or different types of websites that may generate them funds. This is why they do not even care what types of websites show up on the ads. This makes their unwanted software indirectly risky for your OS.

What are the symptoms of .js Files?

There are several symptoms to look for when this particular threat and also unwanted apps in general are active:

Symptom #1: Your computer may become slow and has poor performance in general.

Symtpom #2: You have toolbars, add-ons or extensions on your web browsers that you don't remember adding.

Symptom #3: You see all types of ads, like ad-supported search results, pop-ups and redirects to randomly appear.

Symptom #4: You see installed apps on your Mac running automatically and you do not remember installing them.

Symptom #5: You see suspicious processes running in your Task Manager.

If you see one or more of those symptoms, then security experts reccomend that you check your computer for viruses.

What types of Unwanted Programs are there?

According to most malware researchers and cyber-security experts, the threats that can currently affect your Mac can be the following types:

  • Rogue Antivirus programs.
  • Adware.
  • Browser hijackers.
  • Clickers.
  • Fake optimizers.

What to do if I have a "virus" like .js Files?

Do not panic! You can easily get rid of most adware or unwanted program threats by firstly isolating them and then removing them from your browser and computer. One reccomended way to do that is by using a reputable malware removal software that can take care of the removal automatically for you. There are many anti-malware apps out there that you can choose from. SpyHunter is one of the reccomended anti-malware apps, that can scan your computer for free and detect any viruses, tracking cookies and unwanted adware apps and eliminate them quickly. This saves time when compared to doing the removal manually.

How to secure my passwords and other data from .js Files?

With few simple actions. First and foremost, it is imperative that you follow these steps:

Step 1: Find a safe computer and connect it to another network, not the one that your Mac was infected in.

Step 2: Change all of your passwords, starting from your e-mail passwords.

Step 3: Enable two-factor authentication for protection of your important accounts.

Step 4: Call your bank to change your credit card details (secret code, etc.) if you have saved your credit card for online shopping or have done online activiites with your card.

Step 5: Make sure to call your ISP (Internet provider or carrier) and ask them to change your IP address.

Step 6: Change your Wi-Fi password.

Step 7: (Optional): Make sure to scan all of the devices connected to your network for viruses and repeat these steps for them if they are affected.

Step 8: Install anti-malware software with real-time protection on every device you have.

Step 9: Try not to download software from sites you know nothing about and stay away from low-reputation websites in general.

If you follow these reccomendations, your network and all devices will become significantly more secure against any threats or information invasive software and be virus free and protected in the future too.

More tips you can find on our website, where you can also ask any questions and comment underneath the articles about your computer problems. We will try to respond as fast as possible.

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