System Has Detected Intrusion Scam
Written by Tomas Meskauskas on (updated)
What is System Has Detected Intrusion?
"System Has Detected Intrusion" is a fake error message displayed by a malicious website. Research shows that users visit this website inadvertently - they are redirected by various potentially unwanted programs (PUPs) that infiltrate systems during installation of other software (the "bundling" method).
As well as causing redirects, PUPs also deliver intrusive online advertisements and continually record data relating to users' Internet browsing activity.
The "System Has Detected Intrusion" error message states that a number of DLL files are missing from the Windows folder. In addition, the system might be infected and, therefore, personal information (banking details, logins/passwords, etc.) is at risk.
It states that the problem must be resolved immediately and users are encouraged to contact "certified technicians" via a telephone number ("+1-855-875-1671") provided. They are will then supposedly be guided through the malware removal process.
Be aware, however, that, as mentioned above, the "System Has Detected Intrusion" error is fake. Cyber criminals attempt to scare and trick victims into calling, and paying for technical support that is not required. Therefore, you should never attempt to call the aforementioned telephone number.
You can remove this error simply by closing the web browser. Furthermore, PUPs employ a "virtual layer" to generate coupon, pop-up, banner, and other similar ads. This is a tool that enables placement of third party graphical content on any site.
Therefore, unwanted ads often conceal underlying content of visited websites, thereby significantly diminishing the web browsing experience. In addition, some redirect to malicious websites and even accidental clicks can result in high-risk adware or malware infections.
Furthermore, PUPs continually gather various information that might be personally identifiable. The data (IP addresses, URLs visited, pages viewed, search queries, mouse/keyboard activity, geo-locations, etc.) is shared with third parties (potentially, cyber criminals) who generate revenue by misusing personal details.
Therefore, the presence of data-tracking apps can lead to serious privacy issues or even identity theft. We strongly recommend that you uninstall all potentially unwanted programs immediately.
There are dozens of fake errors virtually identical to "System Has Detected Intrusion". Examples include (but are not limited to) Attempt To Tamper Data on This PC, Suspicious Activity From Your IP Address, Your Windows Has Been Banned, and Your System Might Be Infected.
All claim that the system is damaged in certain ways, however, as with "System Has Detected Intrusion", these error messages are designed to trick users into paying for services that are not required. Potentially unwanted programs are deployed only to generate revenue for the developers.
They often claim to enhance the Internet browsing experience by providing various 'useful features', however, rather than providing any value for regular users, PUPs cause unwanted redirects, gather personal information, and deliver intrusive advertisements.
How did adware install on my computer?
To promote potentially unwanted programs, developers use a deceptive marketing method called "bundling" - stealth installation of third party software with regular apps.
Users often rush the download/installation processes and skip most steps. Therefore, bundled software is hidden within the "Custom/Advanced" settings. By skipping this section, users expose their systems to risk of various infections and compromise their privacy.
How to avoid installation of potentially unwanted applications?
Potentially unwanted programs are distributed using the "bundling" method. Therefore, never rush the download or installation processes. Choose the "Custom/Advanced" settings, observe each step, and decline offers to download/install additional applications.
Text presented within "System Has Detected Intrusion" error:
Warning: system has detected intrusion and root kits or some dll files are missing from c://windows
Please call urgent to Microsoft Certified Technician to get this problem at +1-855-875-1671
Do not ignore this critical alert. If you close this page, your computer access will be disabled to prevent
further damage to our network. You computer has alerted us that it has been infected with a virus and spyware.
The following information is being stolen… Facebook Logins, Credit Card Details, Email Account Login,
Photos stored on this computer. You must contact us immediately so that our engineers can walk you through the removal
process over the phone. Please call us within the next 5 minutes to prevent your computer from being disabled.
Toll Free +1-855-875-1671
Fake "System Has Detected Intrusion" error (GIF):
Instant automatic malware removal:
Manual threat removal might be a lengthy and complicated process that requires advanced IT skills. Combo Cleaner is a professional automatic malware removal tool that is recommended to get rid of malware. Download it by clicking the button below:
▼ DOWNLOAD Combo Cleaner
By downloading any software listed on this website you agree to our Privacy Policy and Terms of Use. To use full-featured product, you have to purchase a license for Combo Cleaner. 7 days free trial available. Combo Cleaner is owned and operated by Rcs Lt, the parent company of PCRisk.com read more.
Quick menu:
- What is System Has Detected Intrusion?
- STEP 1. Uninstall deceptive applications using Control Panel.
- STEP 2. Remove adware from Internet Explorer.
- STEP 3. Remove rogue extensions from Google Chrome.
- STEP 4. Remove potentially unwanted plug-ins from Mozilla Firefox.
- STEP 5. Remove rogue extension from Safari.
- STEP 6. Remove rogue plug-ins from Microsoft Edge.
Adware removal:
Windows 11 users:
Right-click on the Start icon, select Apps and Features. In the opened window search for the application you want to uninstall, after locating it, click on the three vertical dots and select Uninstall.
Windows 10 users:
Right-click in the lower left corner of the screen, in the Quick Access Menu select Control Panel. In the opened window choose Programs and Features.
Windows 7 users:
Click Start (Windows Logo at the bottom left corner of your desktop), choose Control Panel. Locate Programs and click Uninstall a program.
macOS (OSX) users:
Click Finder, in the opened screen select Applications. Drag the app from the Applications folder to the Trash (located in your Dock), then right click the Trash icon and select Empty Trash.
In the uninstall programs window, look for any suspicious/recently-installed applications, select these entries and click "Uninstall" or "Remove".
After uninstalling the potentially unwanted program, scan your computer for any remaining unwanted components or possible malware infections. To scan your computer, use recommended malware removal software.
Remove adware from Internet browsers:
Video showing how to remove potentially unwanted browser add-ons:
Remove malicious add-ons from Internet Explorer:
Click the "gear" icon 
(at the top right corner of Internet Explorer), select "Manage Add-ons". Look for any recently-installed suspicious browser extensions, select these entries and click "Remove".
Optional method:
If you continue to have problems with removal of the "system has detected intrusion" virus, reset your Internet Explorer settings to default.
Windows XP users: Click Start, click Run, in the opened window type inetcpl.cpl In the opened window click the Advanced tab, then click Reset.
Windows Vista and Windows 7 users: Click the Windows logo, in the start search box type inetcpl.cpl and click enter. In the opened window click the Advanced tab, then click Reset.
Windows 8 users: Open Internet Explorer and click the gear icon. Select Internet Options.
In the opened window, select the Advanced tab.
Click the Reset button.
Confirm that you wish to reset Internet Explorer settings to default by clicking the Reset button.
Remove malicious extensions from Google Chrome:
Click the Chrome menu icon 
(at the top right corner of Google Chrome), select "Tools" and click "Extensions". Locate all recently-installed suspicious browser add-ons, select these entries and click the trash can icon.
Optional method:
If you continue to have problems with removal of the "system has detected intrusion" virus, reset your Google Chrome browser settings. Click the Chrome menu icon 
(at the top right corner of Google Chrome) and select Settings. Scroll down to the bottom of the screen. Click the Advanced… link.
After scrolling to the bottom of the screen, click the Reset (Restore settings to their original defaults) button.
In the opened window, confirm that you wish to reset Google Chrome settings to default by clicking the Reset button.
Remove malicious plug-ins from Mozilla Firefox:
Click the Firefox menu 
(at the top right corner of the main window), select "Add-ons". Click "Extensions", in the opened window, remove all recently-installed suspicious browser plug-ins.
Optional method:
Computer users who have problems with "system has detected intrusion" virus removal can reset their Mozilla Firefox settings.
Open Mozilla Firefox, at the top right corner of the main window, click the Firefox menu, in the opened menu, click Help.
Select Troubleshooting Information.
In the opened window, click the Refresh Firefox button.
In the opened window, confirm that you wish to reset Mozilla Firefox settings to default by clicking the Refresh Firefox button.
Remove malicious extensions from Safari:
Make sure your Safari browser is active, click Safari menu, and select Preferences....
In the opened window click Extensions, locate any recently installed suspicious extension, select it and click Uninstall.
Optional method:
Make sure your Safari browser is active and click on Safari menu. From the drop down menu select Clear History and Website Data...
In the opened window select all history and click the Clear History button.
Remove malicious extensions from Microsoft Edge:
Click the Edge menu icon 
(at the upper-right corner of Microsoft Edge), select "Extensions". Locate all recently-installed suspicious browser add-ons and click "Remove" below their names.
Optional method:
If you continue to have problems with removal of the "system has detected intrusion" virus, reset your Microsoft Edge browser settings. Click the Edge menu icon (at the top right corner of Microsoft Edge) and select Settings.
In the opened settings menu select Reset settings.
Select Restore settings to their default values. In the opened window, confirm that you wish to reset Microsoft Edge settings to default by clicking the Reset button.
- If this did not help, follow these alternative instructions explaining how to reset the Microsoft Edge browser.
Summary:
Commonly, adware or potentially unwanted applications infiltrate Internet browsers through free software downloads. Note that the safest source for downloading free software is via developers' websites only. To avoid installation of adware, be very attentive when downloading and installing free software. When installing previously-downloaded free programs, choose the custom or advanced installation options – this step will reveal any potentially unwanted applications listed for installation together with your chosen free program.
Post a comment:
If you have additional information on "system has detected intrusion" virus or it's removal please share your knowledge in the comments section below.
Outstanding!
▼ Show Discussion