Do not click the link in Mail Delivery Failure email scam

Also Known As: possible malware infections
Damage level: Medium

What is Mail Delivery Failure scam?

Usually, scammers use phishing emails to extract sensitive information (for example, usernames, passwords, or other login credentials, credit card details, social security numbers). It is common that they send emails containing links to phishing websites. This particular email is disguised as a letter from the mail delivery system.

Mail Delivery Failure scam email spam campaign

Mail Delivery Failure scam in detail

Scammers behind this email attempt to trick recipients into believing that they have received an email regarding mail delivery failure. More precisely, they try to trick recipients into viewing messages that supposedly could not be delivered due to some fatal errors in the mail delivery system.

The "View Messages" link in this phishing email opens a fake Webmail website used to trick visitors into entering their email address and a password (login credentials for Webmail email service). Two major differences between real and fake Webmail websites are their web addresses and login pages.

It is clear that scammers behind this email are trying to steal login credentials for Webmail accounts. Typically, stolen email accounts are used to deliver malware, send spam, send scams used to trick other users into making money transactions, providing personal information, or for other malicious purposes.

It is also common for stolen accounts to be checked for emails containing personal information, sold to third parties (other cybercriminals) on the dark web. Stolen login credentials could be used to access other accounts as well. Although, scammers succeed at this only when users use the same login credentials for different accounts.

Threat Summary:
Name Mail Delivery Failure Scam
Threat Type Phishing, Scam, Social Engineering, Fraud
Fake Claim Emails cannot be delivered due to fatal errors in the delivery system
Disguise Letter from Webmail service provider
Symptoms Unauthorized online purchases, changed online account passwords, identity theft, illegal access of the computer.
Distribution methods Deceptive emails, rogue online pop-up ads, search engine poisoning techniques, misspelled domains.
Damage Loss of sensitive private information, monetary loss, identity theft.
Malware Removal (Windows)

To eliminate possible malware infections, scan your computer with legitimate antivirus software. Our security researchers recommend using Combo Cleaner.
▼ Download Combo Cleaner
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.

Similarities with other phishing emails

Most phishing emails are disguised as letters from legitimate companies, organizations, or other entities and used to trick recipients into providing some personal information that could be used to steal identities, online accounts, make fraudulent purchases, transactions, distribute malware, or for other purposes.

More examples of phishing emails are "Anti-Spam Policy Violation Email Scam", "Novo Banco Email Scam", "RingCentral Email Scam". It is important to mention that email can be used as a channel to deliver malware. In such cases, cybercriminals use emails to trick recipients into downloading and opening malicious files.

How do spam campaigns infect computers?

Usually, emails used to distribute malware contain a malicious attachment or website link. Recipients install malware on their computers when they open a downloaded malicious file. Typically, cybercriminals attempt to trick recipients into opening malicious MS Office or PDF documents, JavaScript files, executable files like EXE, archive files like ZIP, RAR.

It is important to mention that malicious documents opened with MS Office 2010 and newer versions do not install malware automatically - they infect computers only if users enable editing/content (macros commands) in them. Malicious documents opened with older MS Office versions install malware on computers right after they get opened.

How to avoid installation of malware?

Installed programs have to be updated and activated using tools, functions provided by their official developers. It is never safe to update or activate them with third-party tools - those tools often are used to distribute malware. Also, it not legal to use cracking tools or cracked (pirated) software.

Files and website links in irrelevant emails that are received from unknown, suspicious addresses should not be opened unless there is no reason to suspect that it might not be safe. It is common for website links and attachments in emails of this kind to be used to distribute malicious software.

Programs (and files) should be downloaded from official, trustworthy websites. It is not safe to use third-party downloaders and installers, Peer-to-Peer networks, unofficial websites, and other sources, tools to download or install programs. Those tools, sources can be used to distribute malware too.

A computer should be scanned for threats regularly. It is advisable to scan it with a reputable antivirus or anti-spyware suite. If you've already opened malicious attachments, we recommend running a scan with Combo Cleaner Antivirus for Windows to automatically eliminate infiltrated malware.

Text presented in the "Mail Delivery Failure scam" email letter:

Subject: Warning: message 1lybNF-0002Y8-MJ delayed 72 hours

Mail Delivery Failure notification for “”.
 ----- The following 15 addresses had permanent fatal errors -----

View Messages

The system generated this notice on 7/12/2021 2:42:36 a.m. .

Do not reply to this automated message.This is a user verification, designed to shut down malicious users and other  activities of  robots.

Security Management

Copyright© 2021

Screenshot of the fake Webmail website used to steal login credentials:

mail delivery failure scam phishing website

Another example of mail delivery failure-themed spam email:

Mail delivery failure spam (2021-10-15)

Text presented within:

Subject: Important Mail Error Notification

Message Error - ********

There was an error while delivering incoming messages to your inbox ********.
Your 12 incoming messages stuck on the remote server. This was due to your current logon session error.

Kindly Re-authenticate session below to receive your 12 incoming emails to your inbox.

Note: Unrecovered emails will be deleted permanently to free server clusters.


Registry Team.

******** Registry. All Rights Reserved 2021.

Instant automatic malware removal: Manual threat removal might be a lengthy and complicated process that requires advanced computer 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:

How to remove malware manually?

Manual malware removal is a complicated task - usually it is best to allow antivirus or anti-malware programs to do this automatically. To remove this malware we recommend using Combo Cleaner Antivirus for Windows.

If you wish to remove malware manually, the first step is to identify the name of the malware that you are trying to remove. Here is an example of a suspicious program running on a user's computer:

malicious process running on user's computer sample

If you checked the list of programs running on your computer, for example, using task manager, and identified a program that looks suspicious, you should continue with these steps:

manual malware removal step 1Download a program called Autoruns. This program shows auto-start applications, Registry, and file system locations:

screenshot of autoruns application

manual malware removal step 2Restart your computer into Safe Mode:

Windows XP and Windows 7 users: Start your computer in Safe Mode. Click Start, click Shut Down, click Restart, click OK. During your computer start process, press the F8 key on your keyboard multiple times until you see the Windows Advanced Option menu, and then select Safe Mode with Networking from the list.

Safe Mode with Networking

Video showing how to start Windows 7 in "Safe Mode with Networking":

Windows 8 users: Start Windows 8 is Safe Mode with Networking - Go to Windows 8 Start Screen, type Advanced, in the search results select Settings. Click Advanced startup options, in the opened "General PC Settings" window, select Advanced startup.

Click the "Restart now" button. Your computer will now restart into the "Advanced Startup options menu". Click the "Troubleshoot" button, and then click the "Advanced options" button. In the advanced option screen, click "Startup settings". Click the "Restart" button. Your PC will restart into the Startup Settings screen. Press F5 to boot in Safe Mode with Networking.

Windows 8 Safe Mode with networking

Video showing how to start Windows 8 in "Safe Mode with Networking":

Windows 10 users: Click the Windows logo and select the Power icon. In the opened menu click "Restart" while holding "Shift" button on your keyboard. In the "choose an option" window click on the "Troubleshoot", next select "Advanced options". In the advanced options menu select "Startup Settings" and click on the "Restart" button.

In the following window you should click the "F5" button on your keyboard. This will restart your operating system in safe mode with networking.

windows 10 safe mode with networking

Video showing how to start Windows 10 in "Safe Mode with Networking":


manual malware removal step 3Extract the downloaded archive and run the Autoruns.exe file.

extract autoruns.zip and run autoruns.exe

manual malware removal step 4In the Autoruns application, click "Options" at the top and uncheck "Hide Empty Locations" and "Hide Windows Entries" options. After this procedure, click the "Refresh" icon.

Click 'Options' at the top and uncheck 'Hide Empty Locations' and 'Hide Windows Entries' options

manual malware removal step 5Check the list provided by the Autoruns application and locate the malware file that you want to eliminate.

You should write down its full path and name. Note that some malware hides process names under legitimate Windows process names. At this stage, it is very important to avoid removing system files. After you locate the suspicious program you wish to remove, right click your mouse over its name and choose "Delete".

locate the malware file you want to remove

After removing the malware through the Autoruns application (this ensures that the malware will not run automatically on the next system startup), you should search for the malware name on your computer. Be sure to enable hidden files and folders before proceeding. If you find the filename of the malware, be sure to remove it.

searching for malware file on your computer

Reboot your computer in normal mode. Following these steps should remove any malware from your computer. Note that manual threat removal requires advanced computer skills. If you do not have these skills, leave malware removal to antivirus and anti-malware programs.

These steps might not work with advanced malware infections. As always it is best to prevent infection than try to remove malware later. To keep your computer safe, install the latest operating system updates and use antivirus software. To be sure your computer is free of malware infections, we recommend scanning it with Combo Cleaner Antivirus for Windows.

Click to post a comment

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.

Our malware removal guides are free. However, if you want to support us you can send us a donation.

About PCrisk

PCrisk logo

PCrisk is a cyber security portal, informing Internet users about the latest digital threats. Our content is provided by security experts and professional malware researchers. Read more about us.

Malware activity

Global malware activity level today:

Medium threat activity

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

QR Code
possible malware infections QR code
Scan this QR code to have an easy access removal guide of possible malware infections on your mobile device.
We Recommend:

Get rid of Windows malware infections today:

Download Combo Cleaner

Platform: Windows

Editors' Rating for Combo Cleaner:
Editors ratingOutstanding!

[Back to Top]

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.