Computers viruses, worms, ransomware, etc. are kinds of malicious software that no user should take lightly. On several occasions, we have touched upon security steps that each user should take in order to protect its identity and data. Sadly sometimes even when all precautions are taken some malware can still slip through and wreak havoc. Today we are looking at some of the worst or the best, depending on your view that has indeed wreaked plenty of havoc.
In the list of the 10 most famous computer viruses below, we show the costs, dates, reach, and other key facts. First a note about terms: we use the words “virus” and “worm” interchangeably because most readers search for them that way. But there’s a subtle difference that we explain after the list.
The worst computer virus outbreak in history, Mydoom caused estimated damage of $38 billion in 2004, but its inflation-adjusted cost is actually $52.2 billion. Also known as Novarg, this malware is technically a “worm,” spread by mass emailing. At one point, the Mydoom virus was responsible for 25% of all emails sent.
Mydoom scraped addresses from infected machines, then sent copies of itself to those addresses. It also roped those infected machines into a web of computers called a botnet that performed distributed denial of service (DDoS) attacks. These attacks were intended to shut down a target website or server.
Mydoom is still around today, generating 1% of all phishing emails. That’s no small feat considering the 3.4 billion phishing emails sent each day. By that figure, Mydoom has taken on a life of its own, infecting enough poorly-protected machines to send 1.2 billion copies of itself per year, 16 years after its creation.
Though a $250,000 reward was offered, the developer of this dangerous computer worm was never caught.
Wondering what makes the world’s most secure computers so safe? See the Tech@Work guide: Upgrade to the World's Most Secure and Manageable PC
The 2003 Sobig computer virus is actually another worm. It is second only to the Mydoom virus in its scope. The $30 billion figure is a worldwide total, including Canada, the U.K., the U.S., mainland Europe, and Asia. Several versions of the worm were released in quick succession, named Sobig.A through Sobig.F, with Sobig.F being the most damaging.
This cybercriminal program masqueraded as legitimate computer software attached to emails. It disrupted ticketing at Air Canada and interfered with countless other businesses. Despite its widespread damage, the creator of the successful bug was never caught.
Klez is a close third on the list of the worst computer viruses ever created. With nearly $20 billion in estimated damages, it infected about 7.2% of all computers in 2001, or 7 million PCs. The Klez worm sent fake emails, spoofed recognized senders and, among other things, attempted to deactivate other viruses.
As with other viruses and worms, Klez was released in several variants. It infected files, copied itself, and spread throughout each victim’s network. It hung around for years, with each version more destructive than the last.
Windows has come a long way since most of the computer viruses on this list hit the web. Thankfully, built-in protection with Microsoft Defender is always on the watch.
The year 2000’s ILOVEYOU virus worked by sending a bogus “love letter” that looked like a harmless text file. Like Mydoom, this attacker sent copies of itself to every email address in the infected machine’s contact list. Shortly after its May 4 release, it had spread to more than 10 million PCs.
The virus was created by a college student in the Philippines named Onel de Guzman. Lacking funds, he wrote the virus to steal passwords so he could log into online services he wanted to use for free. He reportedly had no idea how far his creation would spread. This virus is also known as Loveletter.
Need to up your remote work security game before there’s another entry on the list of most deadly computer viruses? See our guide: How to Work Remotely and Securely
The 2017 WannaCry computer virus is ransomware, a virus that takes over your computer (or cloud files) and holds them hostage. The WannaCry ransomware ripped through computers in 150 countries, causing massive productivity losses as businesses, hospitals, and government organizations that didn’t pay were forced to rebuild systems from scratch.
The malware raged like wildfire through 200,000 computers worldwide. It stopped when a 22-year-old security researcher in the U.K. found a way to turn it off. Computers with out-of-date operating systems were hit especially hard. That’s why security experts always recommend updating your systems frequently.
In September 2020, one of the potentially largest computer virus attacks in medical history hit Universal Health Services. The U.S. hospital chain, which has more than 400 locations, was reportedly struck by damaging ransomware. The attack forced the cancellation of surgeries and made healthcare workers switch to paper records.
The Zeus computer virus is an online theft tool that hit the web in 2007. A whitepaper by Unisys three years later estimated that it was behind 44% of all banking malware attacks. By then, it had breached 88% of all Fortune 500 companies, 2,500 organizations total, and 76,000 computers in 196 countries.
The Zeus botnet was a group of programs that worked together to take over machines for a remote “bot master.” It originated in Eastern Europe and was used to transfer money to secret bank accounts. More than 100 members of the crime ring behind the virus, mostly in the U.S., were arrested in 2010. It’s not as prominent today, but some of the virus’ source code lives on in newer botnet viruses and worms.
Zeus caused documented damage of $100 million. But the real cost in terms of lost productivity, removal, and undocumented theft is undoubtedly much higher. A $3 billion estimate, adjusted for inflation, puts this virus at a cost of $3.7 billion in today’s dollars.
First observed in 2001, the Code Red computer virus was yet another worm that penetrated 975,000 hosts. It displayed the words “Hacked by Chinese!” across infected web pages, and it ran entirely in each machine’s memory. In most cases it left no trace in hard drives or other storage.
Financial costs are pegged at $2.4 billion. The virus attacked websites of infected computers and delivered a distributed denial of service (DDoS) attack on the U.S. White House’s website, www.whitehouse.gov. In fact, the White House had to change its IP address to defend against Cod Red.
Can your printer get a virus? See our cool infographic: The State of Printer Security
The SQL Slammer worm cost an estimated $750 million across 200,000 computer users in 2003. This computer virus randomly selected IP addresses, exploiting vulnerabilities and sending itself on to other machines. It used these victim machines to launch a DDoS attack on several internet hosts, significantly slowing internet traffic.
The Slammer worm hit banks in the U.S. and Canada especially hard, taking ATMs offline in many locations. Customers of Toronto’s Imperial Bank of Commerce found themselves unable to access funds. The attack reared its ugly head again in 2016, launching from IP addresses in Ukraine, China, and Mexico.
Thankfully, ransomware attacks like the 2013 CryptoLocker virus have dipped since their 2017 peak. This malware attacked upwards of 250,000 machines by encrypting their files. It displayed a red ransom note informing users that “your important files encryption produced on this computer.” A payment window accompanied the note.
The virus’ creators used a worm called the Gameover Zeus botnet to make and send copies of the CryptoLocker virus. According to a report by security firm Sophos, the average ransomware attack costs a business $133,000. If we estimate that CryptoLocker hit 5,000 companies, that would put its total cost at $665 million.
Where will cybersecurity go next? See our guide: The Future of Cybersecurity
The Sasser worm was written by a 17-year-old German computer science student named Sven Jaschan. He was arrested at the age of 18 in 2004 after a $250,000 bounty was posted for the computer virus’ creator. A friend of Jaschan’s tipped authorities that the youth had penned not only the Sasser worm but also the damaging Netsky.AC attack.
Jaschan was given a suspended sentence after it was found he was a minor when he wrote the malware. The Sasser worm crashed millions of PCs, and though some reports put damages at $18 billion, the relatively low infection rate suggests a more likely cost of $500 million.
Other notable viruses
The top 10 worst computer viruses above are just the ugly tip of a gargantuan digital iceberg. With a million new malware programs popping up every 3 years, we may miss the forest for a few outstanding trees. Here are just a few more viruses that have wreaked havoc over the years:
Mimail: This worm tried to harvest data from infected machines to launch a string of DDoS attacks, but was relatively easy to remove.
Yaha: Yet another worm with several variants, thought to be the result of a cyber-war between Pakistan and India.
Swen: Written in C++, the Swen computer worm disguised itself to look like a 2003 OS update. Its financial cost has been pegged at $10.4 billion, but not reliably.
Storm Worm: This worm showed up in 2007 and attacked millions of computers with an email about approaching bad weather.
Tanatos/Bugbear: A 2002 keylogger virus that targeted financial institutions and spread to 150 countries.
Sircam: A computer worm from 2001 that used counterfeit emails with the subject line, “I send you this file in order to have your advice.”
Explorezip: This worm used fake emails to spread to every machine on thousands of local networks.
Melissa: The most dangerous computer virus in 1999, Melissa sent copies of itself that looked like NSFW pics. The U.S. FBI estimated cleanup and repair costs at $80 million.
Flashback: A Mac-only virus, Flashback infected over 600,000 Macs in 2012 and even infected Apple’s home base in Cupertino, Calif. In 2020, there’s now more malware on Macs than on PCs.
Conficker: This 2009 virus still infects many legacy systems and could do significant damage if it ever activates.
Stuxnet: This worm is reported to have destroyed Iranian nuclear centrifuges by sending damaging instructions.
“An unknown error has occurred: Server error 421” "Could not send your message. Error 421" 421 4.2.1 : (DYN:T1) http://postmaster.info.aol.com/errors/421dynt1.html 421 4.3.1 Out of disk space for temp file 421 4.3.2 All server ports are busy 421 Downstream server error 421 Fork failed 421 Greylisting enabled, please try later “An unknown error has occurred. Subject ‘Testing’, Account: ‘pop.charter.net’, Server: ‘mail.charter.net’, Protocol: SMTP, Server Response: ’421 Message rejected’, Port: 25, Secure(SSL): No, Server Error: 421, Error Number: 0x800CCC67”
A runtime error is commonly an error that's created after the PC is operating software and encounters a problem of some form. For instance, a runtime error like run-time error code 7 reveals an "out of memory" dilemma.
Run-time errors are normally brought on by clashes with TSR (Terminate and Stay Resident) applications or additional operating applications, software problems, storage problems, or pc viruses.
First, enter the run-time error signal into a search engine to see what info you will get about the precise runtime issue you are receiving. Next, end - job all running applications and TSRs to make sure these aren't the origin of the issue. You can certainly do so by obtaining the job manager by striking Control Alt Delete.
In case your issue is regularly occurring with a unique program, go to that system programmer's site and obtain any upgrades and patches. If unavailable, try uninstalling the application involved and reinstalling it.
In the event the issue is occurring with the os, you may consider reinstalling it although it is a huge commitment. A much better idea would be to try a fix for both Windows XP or Windows 2,000. It is possible to fix and scan files by typing : sfc / scannow, heading to the Begin switch, Run, and then pushing enter. Make certain to put an area between sfc and the reduce.
You might have an equipment or storage dilemma if these measures have not resolved your run-time errors. If that is the situation, contact the support of the application under consideration for potential support accompanied by the pc or motherboard manufacturer.
Many run-time problems can be solved by upgrading the application that's creating the problem. This is only because the programmer's frequently releasing patches and improvements for their applications as insects are found and repaired.
Storage problems may frequently be fixed by rebooting the pc. Consider a reboot a short-term repair. Rebooting clears the memory but in case your COMPUTER does not have adequate memory for your applications you're operating, or sufficient hard-drive space you'll immediately run out of memory again. Something less than this sum may cause memory issues since the computer's swap file isn't in a position to expand in dimension as required.
To assess the quantity of free area, available My Computer and right-click on the HDD, generally the D: drive. Select Attributes in the menu and see the disc's ability. Perform the disk clean-up function by following prompts and pressing the Disk Clean-up button, if the room is reduced.
You may be getting run-time errors, in case your storage chip is really failing. Eliminating and changing the awful memory chip will solve the difficulty. If you're encountering other runtime-related errors, like an install runtime issue, try cleaning away the portions of the registry with some software solution.
Generated due to temporary device and Window system conflicts, Error code 14 is a typical Device Manager error. This error code can pop up anytime and usually displayed in the following format:
“This device cannot work properly until you restart your computer. (Code 14)”
Though it is not a fatal error code like the infamous Blue Screen of Death and runtime error codes, nonetheless it is still advisable to repair it immediately before any delay to avoid inconvenience.
It can lower your PC’s performance and hamper you from using certain hardware devices as a result of driver problems.
Error 14 is triggered when your system is unable to correctly read the files and settings which is important for running a certain piece of your PC hardware. Now this conflict may occur due to reasons like outdated, corrupted, or poorly installed drivers. Other causes may include corrupted registry entries.
Simply put, Error code 14 is a good reminder that PC users should pay attention to updating device drivers to ensure healthy systems and optimum PC performance.
The good news is that error code 14 is quite easy to resolve. You don’t have to spend hundreds of dollars to hire a professional programmer to get it fixed. To repair, simply follow the DIY methods listed below.
We have compiled some of the best, proven, and easy to perform solutions for PC users to resolve Device Manager error codes like error code 14. Follow the instructions here to resume the functionality of your PC.
Let’s get started:
Sometimes, an action as simple as rebooting your PC can also resolve technical problems like error code 14. So, before you try any other method, try giving this a shot.
The moment the error code pops on your screen, simply close all the programs running on your system and restart your PC. This refreshes your system settings, processes and services allowing it to run smoothly.
However, if the error still persists, then try other methods given below.
Corrupted registry entry can also trigger error code 14. To resolve delete the corrupted registry entries. For this, go to the start menu and type Regedit. A dialog box will open. Now navigate through the HKEY_LOCAL_MACHINE key. Expand further to locate HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlClass. Once located, now in the right pane click upper filters and then click delete on the edit menu. Click yes when prompted to confirm the deletion.
Now in the right pane, click lower filters. Repeat the same steps as performed to delete upper filters. Confirm deletion and then exit the registry editor. To activate changes, restart your PC. This will hopefully resolve the issue. If the error code pops up on your computer screen, then try method 3.
Drivers are basically software applications that communicate and provide instructions to your system to operate hardware devices.
When these become corrupt or outdated, you start experiencing problems like error code 14. To resolve, locate corrupted drivers and update them. You can do it both manually and automatically. We’ll discuss both ways.
For a manual driver update, go to the start menu, control panel, and then Device Manager. Now go through all devices listed to locate problematic drivers. To identify problematic drivers, look for yellow exclamation marks next to each device. Devices with yellow exclamation marks indicate that driver issues. To repair, right-click on each hardware device and select update driver.
Updating each driver separately and manually is a stressful and frustrating task. This can take a lot of your time. Sometimes, you may also have to download new driver versions from the internet to install perform updates. To avoid the hassle and save time, it is advisable to install a program like DriverFIX.
This user-friendly and intuitive software is based on sophisticated technology featuring an intelligent programming system that automatically detects all your PC drivers in seconds.
Once you install this software on your system, it instantly identifies problematic drivers and matches them to the latest versions. It updates PC drivers immediately thereby resolving the error code 14 problem in a few seconds. It enables accurate installations and ensures that your PC runs at its optimum level.
More importantly, with this software installed on your PC, you don’t have to worry about keeping track of your driver updates anymore. The software updates drivers on a regular basis with new and compatible versions ensuring that your PC functions properly and you don’t experience any type of Device Manager error code. It is easy to use and install. It is compatible with all Windows versions.
Click here to download DriverFIX to resolve error code 14 on your system right away.
net stop wuauserv net start cryptSvc net start bits net start msiserver
net start wuauserv net start cryptSvc net start bits net start msiserver
Error Code 0x8000222 is an error that occurs during the installation process for Windows 10. It is also present in past versions of the software, going all the way back to Windows 7 and even affecting Windows software products, including Microsoft Word, PowerPoint, and other items in the Microsoft Office Suite.
Common symptoms include:
While there are several factors that can contribute to the appearance of Error Code 0x8000222 during the installation process, most of these factors can be addressed using a few high-level methods. These methods do require some advanced knowledge and computing skills, so if you are unable to complete the steps below successfully or do not have confidence in your ability to undertake these methods on your own, contact a qualified computer repair service that is familiar with the Windows 10 installation process.
There are a few different issues that can cause Error Code 0x8000222 to arise during the installation process on your Windows operating system. The first is a corrupted file in your system library or dynamic link library, also called the DLL. The second is interference by your proxy, firewall, or antivirus software that inhibits the machine from being able to access the files that it needs to successfully complete the installation of your Windows operating system or software.
To address and resolve Error Code 0x8000222 on your Windows operating system, regardless of the version of the software that you are using, there are a few steps that you can take. Keep in mind that these steps do require some advanced skills and knowledge about your computer, so if you don’t believe that you can undertake these steps on your own or if the following methods do not fully resolve the issue on your device, talk to a qualified computer repair technician for assistance.
Here are the best ways to address Error Code 0x8000222 on your Windows machine:
Before implementing this method, make sure that a proxy is not active on your computer. To check to see if there is an active proxy, simply press the Windows key together with the “R” key and type in the command “cmd”, then when the prompt opens up, type in the following command: “netsh winhttp import proxy source=ie”. From the box that follows, if you see a message saying that there has been an error writing in the proxy settings and that access has been denied, it means that you can turn off the proxy setting in your Internet Explorer and the error will go away on its own.
If you do not have an active proxy, it is time to check and see whether your DLL dependencies are properly set up. To do so, open up the command prompt again by pressing the Windows key and “R” key at the same time and typing in “cmd”. Once the command prompt is active, simply typing in “regsvr32 Officevalidator.dll”, then attempt to resume your installation once it has been complete.
In some cases, you may need to restart your computer before attempting the Windows installation process.
If the above method did not successfully resolve the problem, you can go into your control panel and turn off any firewalls or antivirus programs that may be interfering with your ability to complete the Windows installation process. Depending on the programs that you use for your antivirus needs, you may need to restart your computer before you reattempt to do the installation process.
You should be able to turn your firewall and antivirus programs back on once the installation process has run through to completion.
In most cases, taking the steps above will fully resolve the appearance of Error Code 0x8000222 on your Windows 10 machine.
If you wish to always have at your disposal a utility tool to fix these Windows 10 and other related issues when they do arise, download and install a powerful automated tool.