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Remove Trojan.U83 (Virus Removal Instructions) - Chrome, Firefox, IE, Edge

removal by Jake Doevan - - | Type: Adware

Trojan.U83 is a non-existent virus name that crooks use to promote their cleverly engineered online scam

Trojan.U83 fake alert

Trojan.U83 is a fake alert that users might encounter when they get redirected to a malicious website. The bogus pop-up claims that Mac users' machines were infected with a trojan[1] on the last web page they visited. Allegedly, the only way to fix the issue is by downloading and installing useless scareware software under the name Mac Heal Pro.

The social engineering attack in most cases starts with adware[2] – these potentially unwanted programs enter users' machines without notice during freeware installation and change settings of Google Chrome, Safari, Mozilla Firefox or other browser and starts displaying pop-ups, deals, offers, banners, in-text links, and other intrusive content. Thus, while browsing the internet, users might randomly encounter Trojan U83 message, which usually catches users off guard.

While experienced users will notice that Applecare Trojan.U83 is a scam immediately, those less computer-savvy individuals might panic and follow the instructions provided by cybercriminals behind the threat. Unfortunately, these actions might result in money loss, personal information disclosure to unknown parties, as well as installation of malicious tools on the macOS.

Name Trojan.U83
Category Adware
Type Scam
Infiltration Software bundling, third-party sites, ads
Symptoms Intrusive ads on all browsers, scam messages claiming virus infection, redirects to phishing sites, etc.
Main dangers Money loss, malware infections, sensitive data leak
Termination Use automatic tools to delete adware or make use of our manual guide below
Recovery and optimization After you terminate the PUP, scan your Mac with Reimage Reimage Cleaner Intego to recover from the infection swiftly

Trojan.U83 virus is not one-of-a-kind, as crooks used multiple other fictional threat names in online scam schemes before, including Tapsnakee.tre456_worm_osx, Adware_pop.exe, and many others. These fake viruses are scams and do not exist in the cybersecurity world.

Trojan.U83 Mac warning states the following:


The last website has infected your computer with a Trojan.U83.

Immediate repair is required. Click Ok to continue.

**If you leave this page your computer is exposed to being permanently damaged.**

If you encounter this or a similar pop-up on your browser, take into consideration that only your anti-malware software is capable of determining whether or not your macOS is infected with viruses. Therefore, you do not need to remove Trojan.U83 but rather an adware that is hiding inside your computer.

Regardless of which fake virus the crooks claim your machine is infected with, the background of the message often claims that “Your System is infected with 3 viruses.” If you proceed with the bogus scan, the site will prompt you to download a fake tool for the alleged Trojan.U83 removal.

Besides the Trojan.U83 scam messages, you might also notice the following adware infection symptoms:

  • Changed homepage, search engine and new tab address;
  • Increased amount of advertisement on sites that you visit;
  • Redirects to dangerous websites;
  • Slowdown of the browser or/and the operating system;
  • Sponsored links at the top of search results;
  • Suspicious shortcuts, bookmarks and other elements added to your device.

Besides, adware often tracks its users and might make use of browser vulnerabilities to inject malware automatically. For that reason, if you have been seeing Trojan.U83 Mac warning, make sure you scan your device with a reputable security application. After that, make use of Reimage Reimage Cleaner Intego for the best results and a swift recovery.

Trojan.U83 scam
Trojan.U83 is a scam that is used by cybercrooks in order to make users believe that their Mac machines are infected with malware and that the only way to remove it is to download bogus software

Ways you could avoid adware and other PUP infections

One of the main reasons why users get convinced by online scams is because they are unaware of how adware operates or why they see these fake messages in the first place. Therefore, to avoid getting scammed by a bogus pop-up or redirect, make sure you research it online, look for grammar or spelling mistakes, aggressive tone of the message (for example, “download XXX of face consequence”), and similar scam signs.[3]

On the other hand, if you will manage to avoid adware, you will be less likely to encounter online scams in the first place. Therefore, you should always pay close attention to the installation process of the new software and decline any deals or offers, remove all the marks from the pre-ticked boxes and always select Advanced/Custom settings instead of Recommended/Quick ones.

Stop Trojan.U83 fake alerts by deleting adware hiding inside your Mac

Virus warning withing browsers are all fake, as only security software that is capable of analyzing malware patterns on your computer can alert you about real threats. Therefore, take that into consideration and never install any software promoted on sites that claim Trojan.U83 virus or another malware intrusion.

To remove Trojan.U83 Mac warnings, you will have to terminate adware that is inside your machine. You can either make use of anti-malware software or delete the threat manually with the help of our detailed step-by-step guide below.

Note that, if you encountered the message just once or twice, it does not mean that adware is present, as you might have been redirected from another site that practices shady advertisement techniques. Therefore, if you are not sure, always scan your device with an anti-virus application.

Once you complete Trojan.U83 removal, you should also reset all the installed browsers in order to delete all the traces of adware.

You may remove virus damage with a help of Reimage Reimage Cleaner Intego. SpyHunter 5Combo Cleaner and Malwarebytes are recommended to detect potentially unwanted programs and viruses with all their files and registry entries that are related to them.

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Reimage Happiness
Intego Happiness
Compatible with Microsoft Windows Supported versions Compatible with OS X Supported versions
What to do if failed?
If you failed to remove virus damage using Reimage Intego, submit a question to our support team and provide as much details as possible.
Reimage Intego has a free limited scanner. Reimage Intego offers more through scan when you purchase its full version. When free scanner detects issues, you can fix them using free manual repairs or you can decide to purchase the full version in order to fix them automatically.
Alternative Software
Different software has a different purpose. If you didn’t succeed in fixing corrupted files with Reimage, try running SpyHunter 5.
Alternative Software
Different software has a different purpose. If you didn’t succeed in fixing corrupted files with Intego, try running Combo Cleaner.

To remove Trojan.U83, follow these steps:

Uninstall Trojan.U83 from Mac OS X system

To stop Trojan.U83 fake messages, perform the following steps on macOS or Mac OS X:

  1. If you are using OS X, click Go button at the top left of the screen and select Applications. Cick 'Go' and select 'Applications'
  2. Wait until you see Applications folder and look for Trojan.U83 or any other suspicious programs on it. Now right click on every of such entries and select Move to Trash. Click on every malicious entry and select 'Move to Trash'

Remove Trojan.U83 from Internet Explorer (IE)

  1. Remove dangerous add-ons
    Open Internet Explorer, click on the Gear icon (IE menu) on the top right corner of the browser and choose Manage Add-ons. Click on menu icon and select 'Manage add-ons'
  2. You will see a Manage Add-ons window. Here, look for Trojan.U83 and other suspicious plugins. Disable these entries by clicking Disable: Right click on each of malicious entries and select 'Disable'
  3. Change your homepage if it was altered by virus:
    Click on the gear icon (menu) on the top right corner of the browser and select Internet Options. Stay in General tab.
  4. Here, remove malicious URL and enter preferable domain name. Click Apply to save changes. Delete malicious URL, enter your desired domain name and click 'Apply' to save changes
  5. Reset Internet Explorer
    Click on the gear icon (menu) again and select Internet options. Go to Advanced tab.
  6. Here, select Reset.
  7. When in the new window, check Delete personal settings and select Reset again to complete Trojan.U83 removal. Go to 'Advanced' tab and click on 'Reset' button. Now select 'Delete personal settings' and click on 'Reset' button again

Eliminate Trojan.U83 from Microsoft Edge

Reset Microsoft Edge settings (Method 1):

  1. Launch Microsoft Edge app and click More (three dots at the top right corner of the screen).
  2. Click Settings to open more options.
  3. Once Settings window shows up, click Choose what to clear button under Clear browsing data option. Go to Settings and select 'Choose what to clear'
  4. Here, select all what you want to remove and click Clear. Select 'Clear' button
  5. Now you should right-click on the Start button (Windows logo). Here, select Task Manager. Open the start menu and select 'Task Manager'
  6. When in Processes tab, search for Microsoft Edge.
  7. Right-click on it and choose Go to details option. If can’t see Go to details option, click More details and repeat previous steps. Right-click 'Microsoft Edge' and select 'Go to details' Select 'More details' if 'Go to details' option fails to show up
  8. When Details tab shows up, find every entry with Microsoft Edge name in it. Right click on each of them and select End Task to end these entries. Find Microsoft Edge entries and select 'End Task'

Resetting Microsoft Edge browser (Method 2):

If Method 1 failed to help you, you need to use an advanced Edge reset method.

  1. Note: you need to backup your data before using this method.
  2. Find this folder on your computer: C:\Users\%username%\AppData\Local\Packages\Microsoft.MicrosoftEdge_8wekyb3d8bbwe.
  3. Select every entry which is saved on it and right click with your mouse. Then Delete option. Go to Microsoft Edge folder on your computer, right-click every entry and click 'Delete'
  4. Click the Start button (Windows logo) and type in window power in Search my stuff line.
  5. Right-click the Windows PowerShell entry and choose Run as administrator. Find Windows PowerShell, right-click it and select 'Run as administrator'
  6. Once Administrator: Windows PowerShell window shows up, paste this command line after PS C:\WINDOWS\system32> and press Enter:
    Get-AppXPackage -AllUsers -Name Microsoft.MicrosoftEdge | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register $($_.InstallLocation)\AppXManifest.xml -Verbose}
    Copy and paste a required command and press 'Enter'

Once these steps are finished, Trojan.U83 should be removed from your Microsoft Edge browser.

Delete Trojan.U83 from Mozilla Firefox (FF)

  1. Remove dangerous extensions
    Open Mozilla Firefox, click on the menu icon (top right corner) and select Add-ons Extensions. Click on menu icon and select 'Add-ons'
  2. Here, select Trojan.U83 and other questionable plugins. Click Remove to delete these entries. Select 'Extensions' and look for malicious entries. Click 'Remove' to get rid of each of them
  3. Reset Mozilla Firefox
    Click on the Firefox menu on the top left and click on the question mark. Here, choose Troubleshooting Information. Click on menu icon and then on '?'. Select 'Troubleshooting Information'
  4. Now you will see Reset Firefox to its default state message with Reset Firefox button. Click this button for several times and complete Trojan.U83 removal. Click on 'Reset Firefox' button for a couple of times

Get rid of Trojan.U83 from Google Chrome

Remember to reset Google Chrome after you delete the PUP:

  1. Delete malicious plugins
    Open Google Chrome, click on the menu icon (top right corner) and select Tools Extensions. Click on menu icon. Select 'Tools' and 'Extensions'
  2. Here, select Trojan.U83 and other malicious plugins and select trash icon to delete these entries. Look for malicious entries and delete each of them by clicking on the Trash bin icon
  3. Click on menu icon again and choose Settings Manage Search engines under the Search section. When in 'Settings', select 'Manage search engines...'
  4. When in Search Engines..., remove malicious search sites. You should leave only Google or your preferred domain name. Click 'X' to remove malicious URLs
  5. Reset Google Chrome
    Click on menu icon on the top right of your Google Chrome and select Settings.
  6. Scroll down to the end of the page and click on Reset browser settings. When in 'Settings', scroll down to 'Reset browser settings' button and click on it
  7. Click Reset to confirm this action and complete Trojan.U83 removal. Click on 'Reset' button to complete your removal

Erase Trojan.U83 from Safari

  1. Remove dangerous extensions
    Open Safari web browser and click on Safari in menu at the top left of the screen. Once you do this, select Preferences. Click on 'Safari' and select 'Preferences'
  2. Here, select Extensions and look for Trojan.U83 or other suspicious entries. Click on the Uninstall button to get rid each of them. Go to 'Extensions' and uninstall malicious add-ons
  3. Reset Safari
    Open Safari browser and click on Safari in menu section at the top left of the screen. Here, select Reset Safari.... Click on 'Safari' and select 'Reset Safari...'
  4. Now you will see a detailed dialog window filled with reset options. All of those options are usually checked, but you can specify which of them you want to reset. Click the Reset button to complete Trojan.U83 removal process. Select all options and click on 'Reset' button

About the author

Jake Doevan
Jake Doevan - Computer technology expert

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