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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.
10 worst computer viruses in historyIn 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.

Quest 2 has been crowned as the best overall VR headset by many websites, and to be honest it is really a great piece of equipment deserving of every praise it gets. It seems that Meta feels that it can do better so the new upcoming Quest Pro is upgraded and a new line of VR sets from this company. The economic standard Quest line will not be shut down and it will still remain as an economic version of Meta's VR product line.

Quest Pro will be added as a new line of the better product line with better performance and better quality. It is the first VR headset that is packing Qualcomm Snapdragon XR3+ Gen 1 chipset, 12GB of RAM, 256GB of internal storage, and 10 high-resolution sensors. Of course, this much power and improvement come with a higher price tag, this time that price tag is $1,499.99.
The new VR headset promises industry-leading visuals with a new optical stack instead of Fresnel lenses in Meta Quest 2 with thin-layer pancake optics that fold light reducing the depth of the optical module by 40% and at the same provides clear and sharp visuals.
The headset will give display more vivid colors, richer colors, and higher contrast by incorporating local dimming and quantum dot technology. It composes of specialized backlight hardware accompanied by software algorithms that can control more than individual LED blocks independently.
The Quest Pro will also come packed with new Meta Quest Touch Pro controllers. They will feature three built-in sensors to track the controller's position completely independent of the headset which means that tracking and range of motion will be improved. These new controllers will also be sold separately at the cost of $299.99 and they can be used with Quest 2.
The headset is available for preorder and it will start shipping in late October on the Meta website
“Windows can’t stop your ‘Generic volume’ device because a program is still using it. Close any programs that might be using the device, and then try again later.”It is possible that the system is still using the external device – for instance, a copy operation might still be in progress, or Windows is still indexing the contents of the drive in the background or it could also be that the drive is not configured to be quickly removed. To fix this error, there are a couple of suggestions you can try. You can try to close all the open programs and file explorer windows, or you could also configure the Device Removal Policy or change its file system to FAT32. In addition, you can also try to change its drive letter or use the DISKPART utility to get the drive to be offline or simply manage the hogging process that prevents it from being safely removed. Follow each one of the given potential fixes below to resolve the error when using the Safely Remove Hardware feature.
Same as in previous Windows versions, Windows 11 will also use certain applications as default ones for opening certain file types and file extensions. And yes, same as in previous versions it will come preconfigured for certain file types and associated applications like for example photos for pictures.
Of course, users usually have their own favorite applications for certain file types and much more prefer to open them inside the application of their choice instead of the default one.
We can change the default application like in previous Windows versions but this time there are two ways and overall more control of this process. Windows 11 has settings for choosing default file type applications and default file extension applications giving you more control of this process.
“Something went wrong You can contact Microsoft support for help with this error. Here is the error code 0xa0000400.”As you know, keeping your computer up to date with all the Windows Updates is important and is imperative especially if you are experiencing a couple of issues like the Windows Upgrade error 0xa0000400. At the time of writing, there is no specific cause that has been found for this error. However, there are some potential fixes that might help you. You can try to recreate the Windows 10 installation USB and get the ISO files or you could also get a newer version of the Windows Media Creation Tool, or turn off your internet connection at a specific time or run the Windows Update troubleshooter. For more details, refer to the options given below.
Antivirus software has become the kind of a must-have in every computer in this day and age. When you think about it, our systems are connected to the internet most of the time if not always, and therefore kind placed in from the line of various cyber-attacks. Here antivirus software comes into focus, especially because it has evolved long from just a simple virus removal tool to full security suites.
We will be going through the best of these applications in order to present both their good and bad sides and hope that we will help you in picking the right one for you. Remember, picking either one of the presented solutions is way better than not having one at all. The list is made from best down in our opinion so number one is highly recommended.
“Oops... the system encountered a problem (#707)” “Server error occurred and your email was not sent (error 707)”
Error Causes
Windows 11 release date is closing in, some people have tried it via insider build, some have decided not to. It has come to our attention that there is a little website made by BlueEdge that offers a virtual Windows 11 desktop.
Opening the Website will put you right inside Windows 11 desktop, now take note that this is not Windows 11, it is a simulation of Microsoft’s newest OS and therefore many things will not work like File Explorer, etc.
One thing you can make sure it is working is UI itself, you can see how you do like the new Taskbar, start menu, widgets, and some other things. You can just pop up on the site and check how you do like the overall new look and feel of Windows 11 UI before installing it or trying it.
We are sure that many more options will come in time but even now you can get a feel of the newest OS.
Windows 11 BlueEdge site: https://win11.blueedge.me/