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Trojan.u83 “Virus” Removal (March 2019 Update)

Parasite may reinstall itself multiple times if you don't delete its core files. We recommend downloading SpyHunter to scan for malicious programs installed with it. This may save you hours and cut down your time to about 15 minutes. 

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This page aims to help you remove Trojan.u83 “Virus”. Our removal instructions work for Safari, Chrome, and Firefox, as well as every version of Macintosh.

Trojan.u83 “Virus” is a scare tactic caused by a browser hijacker. This program acts like a browser hijacker and usually integrates with Chrome, Firefox, Internet Explorer, and other popular browsers and applies certain changes to their homepage or search engine. Very often users are misled into installing Trojan.u83 without knowing it and once it becomes part of their system, they are forced to endure its aggressive methods of advertising which include sudden page redirects, generation of ads, banners, dozens of popping messages, links, offers and blinking boxes. When they try to remove it, however, they face serious difficulties because the program is not uninstalled the usual way. In most of the cases, a detailed removal guide or specialized software is needed to completely remove this software and eliminate all of its changes and pop-ups. If you are on this page to learn how to do that, stay with us until the end because here we have prepared detailed instructions and some very useful information related to Trojan.u83 and similar browser hijackers.  

Is Trojan.u83 a virus?

Due to the aggressive activities and frequent browsing disturbance and redirects, internet users, IT webpages and forums have started calling this program malware. Most of them claim that this program is nothing more than a virus, malware or scam. However, in fact, Trojan.u83 is neither a virus nor a malicious program such as a Trojan horse or a Ransomware. It is a browser hijacker.  Browser hijackers are basically harmless components that serve the online advertising industry and tend to redirect and expose users to different sponsored pages. Still, due to their ad generating behavior and browser modifications, security specialists generally classify this software as a potentially unwanted and recommend users to remove it from their computers if they feel the program is not meeting their expectations or is causing them disturbance. More so, the browser hijacker should be removed from your computer if it came without your knowledge or consent.

Trojan.u83 recently began to trigger more discussions and complaints!

People started complaining that this program appears on their computers without downloading it. For this reason, we have to clarify that the program does not infect your system as a virus because it actually needs your permission to get installed. Trojan.u83 can be downloaded from its official website, other freeware or shareware platforms, free download links, spam messages or software bundles and can often get into the computers with other free software.


Name Trojan.u83
Type Browser Hijacker
Danger Level Medium (nowhere near threats like Ransomware, but still a security risk)
Symptoms Browser redirects, homepage or search engine replacements, generation of various intrusive ads. 
Distribution Method Program bundles, freeware or shareware sites, free download links, ads, spam messages.
Detection Tool

Keep in mind, SpyHunter’s malware detection tool is free. To remove the infection, you’ll need to purchase the full version. More information about SpyHunter and steps to uninstall.

Trojan.u83 “Virus” Removal


To remove parasite on your own, you may have to meddle with system files and registries. If you were to do this, you need to be extremely careful, because you may damage your system.

If you want to avoid the risk, we recommend downloading SpyHunter
a professional malware removal tool.

More information on SpyHunter, steps to uninstallEULAThreat Assessment Criteria, and Privacy Policy.

The first thing you need to do is to Quit Safari (if it is opened). If you have trouble closing it normally, you may need to Force Quit Safari:

You can choose the Apple menu and click on Force Quit.

Alternatively you can simultaneously press (the Command key situated next to the space bar), Option (the key right next to it) and Escape (the key located at the upper left corner of your keyboard).

If you have done it right a dialog box titled Force Quit Applications will open up.

In this new dialog window select Safari, then press the Force Quit button, then confirm with Force Quit again.

Close the dialog box/window.



We get asked this a lot, so we are putting it here: Removing parasite manually may take hours and damage your system in the process. We recommend downloading SpyHunter to see if it can detect parasite files for you.

Start Activity Monitor by opening up Finder, then proceed to activity-monitor

Once there, look at all the processes: if you believe any of them are hijacking your results, or are part of the problem, highlight the process with your mouse, then click the “i” button at the top. This will open up the following box:


Now click on Sample at the bottom:


Do this for all processes you believe are part of the threat, and run any suspicious files in our online virus scanner, then delete the malicious files:

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Maximum file size: 128MB.

This scanner is free and will always remain free for our website's users. You can find its full-page version at:

Scan Results

Virus Scanner Result


The next step is to safely launch Safari again. Press and hold the Shift key while relaunching Safari. This will prevent Safari’s previously opened pages from loading again. Once Safari is opened up, you can release the Shift key.

On the off chance that you are still having trouble with scripts interrupting the closing of unwanted pages in Safari, you may need to take some additional measures.

First, Force Quit Safari again.

Now if you are using a Wi-Fi connection turn it off by selecting Wi-Fi off in you Mac’s Menu. If you are using a cable internet (Ethernet connection), disconnect the Ethernet cable.


Re-Launch Safari but don’t forget to press and hold the Shift button while doing it, so no previous pages can be opened up. Now, Click on Preferences in the Safari menu,

Preferences in Safari

and then again on the Extensions tab,

extensions in safari

Select and Uninstall any extensions that you don’t recognize by clicking on the Uninstall button. If you are not sure and don’t want to take any risks you can safely uninstall all extensions, none are required for normal system operation.

The threat has likely infected all of your browsers. The instructions below need to be applied for all browsers you are using.

Again select Preferences in the Safari Menu, but this time click on the Privacy tab,
Privacy in Safari

Now click on Remove All Website Data, confirm with Remove Now. Keep in mind that after you do this all stored website data will be deleted. You will need to sign-in again for all websites that require any form of authentication.

Still in the Preferences menu, hit the General tab

General Tab in Safari

Check if your Homepage is the one you have selected, if not change it to whatever you prefer.
Default Home Page

Select the History menu this time, and click on Clear History. This way you will prevent accidentally opening a problematic web page again.

firefox-512 How to Remove Trojan.u83 From Firefox in OSX:

Open Firefoxclick on mozilla menu (top right) ——-> Add-onsHit Extensions next.

pic 6

The problem should be lurking somewhere around here –  Remove it. Then Refresh Your Firefox Settings.

chrome-logo-transparent-backgroundHow to Remove Trojan.u83 From Chrome in OSX:

 Start Chrome, click chrome menu icon —–>More Tools —–> Extensions. There,  find the malware and  select  chrome-trash-icon.

pic 8

 Click chrome menu icon again, and proceed to Settings —> Search, the fourth tab, select Manage Search Engines.  Delete everything but the search engines you normally use. After that Reset Your Chrome Settings.


Different ad campaigns are spreading free software packages, and they often group some attractive or new applications with ad-generating components or similar browser hijacking applications. The users tend to download and install such packs (or bundles) on their computers without carefully customizing them and this is how they end up with some potentially unwanted programs. Therefore, we recommend that you avoid software bundles or shady free installers. In addition, it’s a good idea to start checking free software before downloading it to your computer. To make sure that the “selectable downloadable components” are not added to the program you select, choose either the “Advanced” or “Custom” settings and carefully check each bookmark and uncheck any additional programs.

In case that some irritating pop-up ads, redirects, and annoying new search engines have already started to disturb you, take the necessary steps to uninstall Trojan.u83. At the end of the page, you will find a detailed removal guide on that. If you don’t do that, the browser hijacker will start showing you annoying and intrusive pop-up ads. These ads may tell you about different things, ranging from commercial offers, discounts, and discount codes. Most users claim that after clicking on them they have been redirected to web pages that advertise certain products or contain some sketchy content. No matter what a pop-up ad has reached you, we do not recommend that you open any of them because you may be misled to some insecure web locations or bump into nasty virus infections such as Ransomware, Trojans, and others. To eliminate such risk, we advise you to ignore all the content this program provides and remove it immediately.

Tips for removing Trojan.u83 “Virus”

A virus is definitely not the most appropriate description for Trojan.u83, but its presence in the computer can really be considered parasitic. Complete removal of the browser hijacker is difficult to implement because the program spreads residual files throughout the computer. Although these files may not necessarily be malicious, they take up space and clutter the computer. Cleaning the system from such files is possible but you should be very careful when detecting and deleting them because there is a risk of deleting something vital for the OS. For this reason, it is good to trust professional tools or a detailed removal guide like the one below.


Name Trojan.u83
Type Browser Hijacker
Danger Level Medium (nowhere near threats like Ransomware, but still a security risk)
Symptoms Browser redirects, homepage or search engine replacements, generation of various intrusive ads.
Distribution Method Program bundles, freeware or shareware sites, free download links, ads, spam messages.
Detection Tool

Keep in mind, SpyHunter’s malware detection tool is free. To remove the infection, you’ll need to purchase the full version. More information about SpyHunter and steps to uninstall.

If the guide doesn’t help, download the anti-virus program we recommended or try our free online virus scanner. Also, you can always ask us in the comments for help!


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