Avoid getting scammed by sites displaying "Error MS-77X1"

Also Known As: Error MS-77X1 (Fehler # MS-77X1) tech support scam
Distribution: Low
Damage level: Medium

"Error MS-77X1" scam removal instructions

What is "Error MS-77X1"?

"Error MS-77X1", also known as "Fehler # MS-77X1", is a technical support scam, run on deceptive sites. The scheme claims that suspicious activity has been detected on the device and due to this - it has been blocked. To resolve the nonexistent issues users are urged to call a fake "Windows Support" helpline. To fabricate the system being locked, "Error MS-77X1" scam automatically turns on printing, so that users would be prevented from closing its webpage. It must be emphasized that all of the information provided by this scheme is false and it is in no way associated with the Microsoft Corporation. Most users access deceptive websites through redirects caused by intrusive advertisements or by PUAs (Potentially Unwanted Applications), already installed onto the system.

Error MS-77X1 scam

The text presented in the "Error MS-77X1" scam is in German. According to a rough translation, it claims that Windows has been blocked due to suspicious activity, and users' browsing history, log-in credentials (i.e. usernames and passwords), credit card details and stored files - are at risk. Users are warned not to ignore this alert, as if they do not call the provided telephone number - the access will be disabled, in order to prevent further damage to the network. The message in the pop-up window, displayed by the "Error MS-77X1" scam, similarly pushes users into calling the fake tech support. It reiterates that the device will be blocked, if users do not call and address the detected threats/issues. Schemes of this type are designed to generate profit by abusing users' trust. Scammers typically attempt to gain access to devices and if they are successful - they can infect the systems with malware (e.g. trojans, ransomware, etc.) and extract sensitive information. Users may be asked to provide their personal information as well. Information of interest includes (but is not limited to): names, addresses, emails, banking account and/or credit card details. The "services" of scammers are expensive and users are requested to pay for them. Often the payments are made via dubious payment portals (which may record the entered banking information) and/or difficult/impossible to trace digital currencies (e.g. cryptocurrencies, pre-paid vouchers, gift cards, etc.). Furthermore, successfully scammed victims can be targeted repeatedly. To summarize, trusting the "Error MS-77X1" scheme can result in system infections, significant financial losses, severe privacy issues and even identity theft. As mentioned in the introduction, the websites running "Error MS-77X1" prevent users from closing them - by displaying printer dialog windows. To close such a site, the Windows Task Manager must be used to end the browser's process. Additionally, when the browser is reopened - the previous browsing session must not be restored, as that will also reopen the scam webpage.

PUAs are one of the main culprits behind rogue redirects to various highly questionable pages. However, these applications can have other/additional functionalities. Unwanted apps classified as adware - deliver intrusive advertisements (e.g. pop-ups, banners, coupons, etc.). Another type called browser hijackers - make modifications to browser settings in order to promote illegitimate search engines. What is more, most types of PUAs have data tracking abilities. They can monitor browsing activity (browsing and search engine histories) and collect personal information extracted from it (IP addresses, geolocations and other details). This vulnerable data is then monetized by being shared with and/or sold to third parties (potentially, cyber criminals). Therefore, it is strongly advised to eliminate all suspicious applications and browser extensions/plug-ins without delay.

Threat Summary:
Name Error MS-77X1 (Fehler # MS-77X1) tech support scam
Threat Type Phishing, Scam, Social Engineering, Fraud
Fake Claim Scam claims the device has been locked, due to suspicious activity detected on it.
Disguise Windows support
Tech Support Scammer Phone Number 0800-101-202
Symptoms Fake error messages, fake system warnings, pop-up errors, hoax computer scan.
Distribution methods Compromised websites, rogue online pop-up ads, potentially unwanted applications.
Damage Loss of sensitive private information, monetary loss, identity theft, possible malware infections.
Malware Removal (Windows)

To eliminate possible malware infections, scan your computer with legitimate antivirus software. Our security researchers recommend using Malwarebytes.
▼ Download Malwarebytes
To use full-featured product, you have to purchase a license for Malwarebytes. 14 days free trial available.

"Covid19 Warning Alert", "Windows Alert & Warning" and "System Activation KEY Has Expired" are a few examples of other technical support scams. There are hundreds of thousands of deceptive websites on the Internet. The schemes make various claims, offers, requests and demands. Popular models include: warnings that the system is infected, alerts that a piece of software is outdated, fake prize giveaways and raffles, ludicrous deals, and so on. Regardless of how scams operate, their end-goals are the same - to generate revenue for the developers.

How did potentially unwanted applications install on my computer?

Some PUAs have "official" download pages, which are often promoted by scam sites. These applications are also distributed via download/installation setups of other products. This false marketing technique of packing regular software with unwanted or malicious additions - is called "bundling". Rushed downloads/installations (e.g. ignored terms, used presets, etc.) - increase the risk of unintentionally allowing bundled content into the device. Once clicked on, intrusive adverts can execute scripts to download/install PUAs.

How to avoid installation of potentially unwanted applications?

It is recommended to research products before download/installation. Only official and verified download channels must be used. Untrustworthy sources, e.g. unofficial and free file-hosting websites, Peer-to-Peer sharing networks and other third party downloaders - commonly offer deceptive and/or bundled content. When downloading/installing, it is advised to read terms, study all possible options, use the "Custom/Advanced" settings and opt-out from supplementary apps, tools, features and other additions. Intrusive ads appear ordinary, however they redirect to dubious webpages (e.g. gambling, pornography, adult-dating, and so on). Should users experience advertisements and/or redirects of this kind, they must inspect their devices and immediately remove all suspect applications and browser hijackers/plug-ins. If your computer is already infected with PUAs, we recommend running a scan with Malwarebytes for Windows to automatically eliminate them.

Text presented in the "Error MS-77X1" scam:

Background:

 

Aufgezeichneter Fehler à:
Windows gemeldeter Download à hxxps://HD-SE***.COM
** WARNUNG KRITISCHE MELDUNG ! **
Fehler # MS-77X1
Windows-Support kontaktieren: 0800-101-202 :
Ignorieren Sie diese wichtige Warnung nicht
Windows wurde aufgrund verdächtiger Aktivitäten blockiert.
Bitte rufen Sie uns innerhalb von 5 Minuten an, um zu
verhindern, dass Ihr Computer deaktiviert wird. Die folgenden
Informationen können verloren gehen:
1. Passwörter
2. Browserverlauf
3. Wichtige Informationen (Kreditkarten)
4. Dateien auf der Festplatte
Ignorieren Sie diese kritische Warnung nicht Wenn Sie diese
Seite schließen, wird Ihr Computerzugriff deaktiviert, um
weitere Schäden an unserem Netzwerk zu verhindern .

 

----------------------

 

Pop-up:

 

Windows-Support kontaktieren: 0800-101-202
Bitte rufen Sie uns an: 0800-101-202
Program firefox.exe
Verified Publisher: Mozilla
Notwendige Maßnahmen:
Kontaktieren Sie uns sofort, damit Unsere
Technikern die Fehler selbst sehen und überprüfen
können. Bitter rufen Sie uns innerhalb 5 minuten an,
um es zu verhindern, sonst Ihr Computer deaktiviert
wird.
Ok Jetzt anrufen
Verhindern Sie zusätzliche Dialoge.

 

Windows-Support kontaktieren: 0800-101-202
0800-101-202

The appearance of "Error MS-77X1" scam (GIF):

Appearance of Error MS-77X1 scam

English variant of "Error MS-77X1" pop-up scam:

Error MS-77X1 POP-UP Scam English variant

Text presented within:

** WARNING CRITICAL MESSAGE**
Error # MS-77X1
Contact Windows Support: +1-855-980-0200 :
Do not ignore this important warning
Windows was blocked due to suspicious activity. Please call us within 5 Minutes to prevent your Computer from being deactivated. The following information may be lost:

1. Passwords
2.  Browsing History     
3. Sensitive information (credit cards)
4.  Files  on the  hard drive  

Do not ignore this critical warning  if you close this page, your Computer access disabled to prevent further damage to our network  .
Contact Windows Support:     
+1-855-980-0200
Contact Windows Support: +1-855-980-0200
Please call us: +1-855-980-0200
Program    firefox.exe
Verified Publisher:    Mozilla
 
Necessary measures:    Contact us immediately so that our technicians can guide you through the process of removing the Phone can lead. Please call us within 5 minutes to prevent Your Computer will be disabled.
Ok Call now
Prevent additional dialogs.
+1-855-980-0200 Recorded error à:
 Windows reported  Download à

Appearance of the English variant (GIF):

Error MS-77X1 POP-UP Scam English variant (GIF)

Instant automatic malware removal: Manual threat removal might be a lengthy and complicated process that requires advanced computer skills. Malwarebytes is a professional automatic malware removal tool that is recommended to get rid of malware. Download it by clicking the button below:
▼ DOWNLOAD Malwarebytes 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 Malwarebytes. 14 days free trial available.

Quick menu:

Removal of potentially unwanted applications:

Windows 7 users:

Accessing Programs and Features (uninstall) in Windows 7

Click Start (Windows Logo at the bottom left corner of your desktop), choose Control Panel. Locate Programs and click Uninstall a program.

Windows XP users:

Accessing Add or Remove Programs in Windows XP

Click Start, choose Settings and click Control Panel. Locate and click Add or Remove Programs.

Windows 10 and Windows 8 users:

Accessing Programs and Features (uninstall) in Windows 8

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.

Mac OSX users:

Uninstall app in OSX (Mac)

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.

PUAs uninstall via Control Panel

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 application, scan your computer for any remaining unwanted components or possible malware infections. To scan your computer, use recommended malware removal software.

Remove rogue extensions from Internet browsers:

Video showing how to remove potentially unwanted browser add-ons:

Internet Explorer logoRemove malicious add-ons from Internet Explorer:

Removing rogue extensions from Internet Explorer step 1

Click the "gear" icon Internet Explorer options 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".

Removing rogue extensions from Internet Explorer step 2

Optional method:

If you continue to have problems with removal of the error ms-77x1 (fehler # ms-77x1) tech support scam, 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.

Resetting Internet Explorer settings to default on Windows XP

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.

Resetting Internet Explorer settings to default on Windows 7

Windows 8 users: Open Internet Explorer and click the gear icon. Select Internet Options.

Reseting Internet Explorer settings to default in Windows 8 - accessing

In the opened window, select the Advanced tab.

Resetting Internet Explorer settings to default on Windows 8 - Internet options advanced tab

Click the Reset button.

Resetting Internet Explorer settings to default on Windows 8 - click the Reset button in the Internet options advanced tab

Confirm that you wish to reset Internet Explorer settings to default by clicking the Reset button.

Resetting Internet Explorer settings to default on Windows 8 - confirm settings reset to default by clicking the reset button

Google Chrome logoRemove malicious extensions from Google Chrome:

Removing rogue extensions from Google Chrome step 1

Click the Chrome menu icon Google Chrome menu icon (at the top right corner of Google Chrome), select "More tools" and click "Extensions". Locate all recently-installed suspicious browser add-ons and remove them.

Removing rogue extensions from Google Chrome step 2

Optional method:

If you continue to have problems with removal of the error ms-77x1 (fehler # ms-77x1) tech support scam, reset your Google Chrome browser settings. Click the Chrome menu icon Google 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.

Google Chrome settings reset step 1

After scrolling to the bottom of the screen, click the Reset (Restore settings to their original defaults) button.

Google Chrome settings reset step 2

In the opened window, confirm that you wish to reset Google Chrome settings to default by clicking the Reset button.

Google Chrome settings reset step 3

Mozilla Firefox logoRemove malicious plugins from Mozilla Firefox:

Removing rogue extensions from Mozilla Firefox step 1

Click the Firefox menu firefox menu icon (at the top right corner of the main window), select "Add-ons". Click on "Extensions", in the opened window remove all recently-installed suspicious browser plug-ins.

Removing rogue extensions from Mozilla Firefox step 2

Optional method:

Computer users who have problems with error ms-77x1 (fehler # ms-77x1) tech support scam removal can reset their Mozilla Firefox settings.

Open Mozilla Firefox, at the top right corner of the main window, click the Firefox menu, firefox menu icon in the opened menu, click Help.

Accessing settings (Reset Firefox to default settings step 1)

Select Troubleshooting Information.

Accessing Troubleshooting Information (Reset Firefox to default settings step 2)

In the opened window, click the Refresh Firefox button.

Clicking on Refresh Firefox button (Reset Firefox to default settings step 3)

In the opened window, confirm that you wish to reset Mozilla Firefox settings to default by clicking the Refresh Firefox button.

Confirm your want to reset Firefox settings to default (Reset Firefox to default settings step 4)

safari browser logoRemove malicious extensions from Safari:

removing adware from safari step 1 - accessing preferences

Make sure your Safari browser is active, click Safari menu, and select Preferences....

removing adware from safari step 2 - removing extensions

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...

resetting safari step 1

In the opened window select all history and click the Clear History button.

resetting safari step 2

Microsoft Edge (Chromium) logoRemove malicious extensions from Microsoft Edge:

Removing adware from Microsoft Edge step 1

Click the Edge menu icon Microsoft Edge (chromium) 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.

Removing adware from Microsoft Edge step 2

Optional method:

If you continue to have problems with removal of the error ms-77x1 (fehler # ms-77x1) tech support scam, reset your Microsoft Edge browser settings. Click the Edge menu icon Microsoft Edge (chromium) menu icon (at the top right corner of Microsoft Edge) and select Settings.

Microsoft Edge (Chromium) reset step 1

In the opened settings menu select Reset settings.

Microsoft Edge (Chromium) reset step 2

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.

Microsoft Edge (Chromium) reset step 3

  • If this did not help, follow these alternative instructions explaining how to reset the Microsoft Edge browser.

Summary:

declining installation of adware while downloading free software sampleCommonly, 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.

Removal assistance:
If you are experiencing problems while trying to remove error ms-77x1 (fehler # ms-77x1) tech support scam from your computer, please ask for assistance in our malware support forum.

Post a comment:
If you have additional information on error ms-77x1 (fehler # ms-77x1) tech support scam or it's removal please share your knowledge in the comments section below.

About the author:

Tomas Meskauskas

Tomas Meskauskas - expert security researcher, professional malware analyst.

I am passionate about computer security and technology. I have an experience of over 10 years working in various companies related to computer technical issue solving and Internet security. I have been working as an author and editor for pcrisk.com since 2010. Follow me on Twitter and LinkedIn to stay informed about the latest online security threats. Contact Tomas Meskauskas.

PCrisk security portal is brought by a company RCS LT. Joined forces of security researchers help educate computer users about the latest online security threats. More information about the company RCS LT.

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Removal Instructions in other languages
Malware activity

Global malware activity level today:

Medium threat activity

Increased attack rate of infections detected within the last 24 hours.

QR Code
Error MS-77X1 (Fehler # MS-77X1) tech support scam QR code
A QR code (Quick Response Code) is a machine-readable code which stores URLs and other information. This code can be read using a camera on a smartphone or a tablet. Scan this QR code to have an easy access removal guide of Error MS-77X1 (Fehler # MS-77X1) tech support scam on your mobile device.
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