What is a virus?
A computer virus is a way of describing a computer programme that has been written specifically to cause damage to your PC. In essence, it is a piece of software that is written to cause as much havoc as possible. A virus is designed to gain access to files or programs on your PC. The virus may enter your computer CD, DVD, USB by email or by your internet connection. There are many types of viruses including worms, phishing, rootkits, and Trojan horses. They are collectively known as malware. An antivirus software package is designed to prevent viruses or malware from damaging your PC. I t does this by being able to recognise emails and programmes which are potentially harmful to your PC and then destroy them. A computer virus is a computer program that can copy itself itsel f [1] and infect a computer. The term "virus" is also commonly but erroneously used to refer to other types of malware malware,, including but not limited to adware and spyware spyware programs programs that do not have the reproductive ability. A true virus can spread from one computer to another (in some form of executable code code)) when its host is taken to the target computer; for instance because a user sent it over a network or the Internet, or carried it on a removable medium such as a floppy disk , CD CD,, DVD DVD,, or USB or USB drive. drive.[2] Viruses can increase their chances of spreading to other computers by infecting files on a network file system or a file system that is accessed by another computer .[3][4]
What is a computer virus?
A computer virus is a small software program that spreads from one computer to another computer and that interferes with computer operation. A computer virus may corrupt or delete data on a computer, use an e-mail program to spread the virus to other computers, or even delete everything on the hard disk. Computer viruses are most easily spread by attachments in e-mail messages or by instant messaging messages. messages. Therefore, you must never open an e-mail attachment unless you know who sent the message or unless you are expecting the e-mail attachment. Computer viruses can be disguised as attachments of funny images, greeting cards, or audio and video files. Computer viruses also spread by using downloads on the Internet. Computer viruses can be hidden in pirated software or in other files or programs that you may download.
Symptoms that may be the result of ordinary Windows functions
A computer virus infection may cause the following problems: •
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Windows does not start even though you have not made any system changes or even though you have not installed or removed any programs. There is frequent modem activity. If you have an external modem, you may notice the lights blinking frequently when the modem is not being used. You may be unknowingly supplying pirated software. Windows does not start because certain important system files are missing. Additionally, you receive an error message that lists the missing f iles.
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The computer sometimes starts as expected. However, at other times, the computer stops responding before the desktop icons and the taskbar appear.
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The computer runs very slowly. Additionally, the computer takes longer than expected to start.
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You receive out-of-memory error messages even though t he computer has sufficient RAM. New programs are installed incorrectly. Windows spontaneously restarts unexpectedly. Programs that used to run stop r esponding frequently. frequently. Even if you remove and reinstall the programs, the issue continues to occur.
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A disk utility such as Scandisk reports multiple serious disk errors.
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A partition disappears.
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The computer always stops responding when you try to use Microsoft Office products.
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You cannot start Windows Task Manager.
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Antivirus software indicates that a computer virus is present.
There are many different symptoms of a virus-infected computer. Some viruses work quickly to damage your computer, while others can linger for months before you notice there is any rea l problem. Some viruses will start to copy themselves within your computer and use up disk space and system memory - slowing down your computer and degrading your system's performance.
Other viruses can be more serious and erase programs, corrupt or destroy selected files or cause a complete system crash. There are also viruses that can open a backdoor to hackers and allow them to access your computer.
How to remove a computer virus To Even for an expert, removing a computer virus can be a difficult task without the help of
computer virus removal tools. Some computer viruses and other unwanted software, such as spyware, even reinstall themselves after the viruses have been detected and removed. Fortunately, by updating the computer and by using antivirus tools, you can help Even for an expert, removing a computer virus can be a difficult task without the help of computer virus removal tools. Some computer viruses and other unwanted software, such as spyware, even reinstall themselves after the viruses have been detected and removed. Fortunately, by updating the computer and by using antivirus tools, you can help Install the latest updates from Microsoft Update on the computer. 1.
Update the antiv irus software on the computer. Then, perform a thorough scan of the computer by using the antivirus software.
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Download, install, and then run the Microsoft Malicious Software Removal Tool to remove existing viruses on the computer. To download the Malicious Software Removal Tool, visit the following Microsoft Web site:
How to protect your computer against viruses To protect your computer against viruses, follow these steps:
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O n t he c om pu te r , t ur n o n t he f ir ew al l.
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Keep the computer operating system up-to-date.
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Use updated antivirus software on the computer.
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Use updated antispyware software on the computer.
How to avoid infecting your Computer (Best Practices):
Anyone that has a computer knows the fear that Computer Viruses can invoke; crashed computers, infected files, loss of information. Fortunately, though computer viruses continue to evolve, so does anti-virus protection. Protecting your computer from these harmful programs is actually quite simple and easy to do with just a few simple practices. Have Anti-Virus Software, Anti-Spyware & Firewall: The first thing you need to do in order to protect you computer from computer viruses is to install a good anti-virus protection system. This generally consists of good anti-virus software, a spyware program and firewall. All computer viruses work differently, and there are some programs that aren't actually viruses at all but can do damage none the less. An anti-virus program may not pick up these programs, so it's best to install all safety procedures you possibly can. Make sure that you choose a good system, that is reliable and known to provide protection. Some of these systems can be a little pricey, but are definitely worth it when you consider all that they can protect your operating system from. Careful what you Download: Many computer viruses and other damaging programs these days are contracted by means of the Internet. A person should always practice good safety measures when on the Internet to avoid infection. Having your anti-virus program in place is of course the first step in keeping your computer running safely. But there are also other steps involved when you a re on the world wide web. You should avoid downloading files and programs from the Internet that you are not familiar with. This is one of the top ways that infected files can get into your computer. If you have a good anti-virus system in place (see article: How Anti-Virus Works for details on how the software works), it should catch these infected files and stop you with a warning. However, they can have a hard time catching newly designed viruses, so your safest option is to be mindful of what you download. Careful of Email Attachments & Instant Messaging: Catching a virus through email or instant messaging is another way that many computers get infected. Again, it cannot be stressed enough how having a good a nti-virus program is the most important part of avoiding these files. However even with one i n place, you should be cautious of files you open through email or instant messenger as these ca n infect your computer. Try and avoid opening emails from people you do not know, and from downloading files from emails a nd instant messenger. Some of these viruses can even come through making you believe it is from someone that you know. Protecting your computer system from harmful computer programs is really quite simple and just takes a little bit of caution a nd attention. If you want your computer system to run smoothly, taking the time to follow these few simple steps will help protect you and you won't have to worry so much about your computer being damaged or corrupted.
What is a Computer Firewall?
A Firewall is a computer program that monitors the flow of information from the Internet to your computer. There are two different types of firewall available for you to use Hardware Firewalls and Software Firewalls. Hardware Firewall: A Hardware Firewall is a physical piece of equipment that sits between the Internet and your computer. An example of a hardware firewall is a broadband router, a common form of Internet connection. The benefit of using a hardware firewall, is that it has the ability to protect multiple computer systems that are connected to it at the same time. This makes it an effective firewall for use in businesses that have multiple computers connected to the Internet, as well as in homes that have more than one computer system. Software Firewall:
work in the same way as a hardware firewall, by monitoring and blocking i nformation that comes to your computer via the Internet, however software firewalls must be installed as a program on your computer. These software firewalls can either be installed from a computer disk that you have purchased, or downloaded over the Internet. Software firewalls are the most common type of firewall. Programs such as Norton 360, Norton Internet Security, ESET Different Types of Computer Viruses Software Firewalls
There are Different Types of Computer Viruses could be classified in (origin, techniques, types of files they infect, where they hide, the kind of damage they cause, the type of operating system or platform they attack) etc. Let us have a look at them…
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Computer Virus is a kind of malicious software w ritten intentionally to enter a computer without the user’s permission or knowledge, with an ability to replica te itself, thus continuing to spread. Some viruses do little but replicate others can ca use severe harm or adversely effect program and performance of the system. A virus should never be assumed harmless and left on a system. Most common types of viruses are mentioned below: Resident Viruses This type of virus is a permanent which dwells in the RAM memory. From there it can overcome and interrupt all of the operations executed by the system: corrupting files a nd programs that are opened, closed, copied, renamed etc. Examples include: Randex, CMJ, Meve, and MrKlunky.
Direct Action Viruses The main purpose of this virus is to re plicate and take action when it is executed. When a specific condition is met, the virus will go into action and infect files in the directory or folder that it is in and in directories that are specified in the AUTOEXEC.BAT file PATH. This batch file is always located in the root directory of the hard disk and carries out certain operations when the computer is booted. Overwrite Viruses Virus of this kind is characterized by the fact that it deletes the information contained in the files that it infects, rendering them partially or totally useless once they have been infected. The only way to clean a file infected by an overwrite virus is to delete the file completely, thus losing the original content. Examples of this virus include: Way, Trj.Reboot, Trivial.88.D. Boot Virus This type of virus affects the boot sector of a floppy or hard disk. This is a crucial part of a disk, in which information on the disk itself is stored together with a program that makes it possible to boot (start) the computer from the disk. The best way of avoiding boot viruses is to ensure that floppy disks are write-protected and never start your computer with an unknown floppy disk in the disk drive. Examples of boot viruses include: Polyboot.B, AntiEXE. Macro Virus Macro viruses infect files that are created using ce rtain applications or programs that contain macros. These mini-programs make it possible to automate series of operations so that they are performed as a single action, thereby saving the user from having to carry them out one by one. Examples of macro viruses: Relax, Melissa.A, Bablas, O97M/Y2K. Directory Virus Directory viruses change the paths that indicate the location of a file. By executing a program (file with the extension .EXE or .COM) which has been infected by a virus, you are unknowingly running the virus program, while the original file and program have been previously moved by the virus. Once infected it becomes impossible to locate the original files. Polymorphic Virus Polymorphic viruses encrypt or encode themselves in a different way (using different algorithms and encryption keys) every time they infect a system. This makes it impossible for anti-viruses to find them using string or signature searches (because they are different in each encryption) and also enables them to create a large number of copies of themselves. Examples include: Elkern, Marburg, Satan Bug, and Tuareg. File Infectors This type of virus infects programs or executable files (files with an .EXE or .COM extension). When one of these programs is run, directly or indirectly, the virus is activated, producing the damaging effects it is programmed to carry out. The ma jority of existing viruses belong to this category, and can be classified depending on the actions that they carry out. Companion Viruses Companion viruses can be considered file infector viruses like resident or direct action types. They are known as companion viruses because once they get into the system they "accompany" the other files that already exist. In other words, in order to carry out their infection routines, companion viruses can wait in memory until a program is run (resident viruses) or act immediately by making copies of themselves (direct action viruses).
How to Get Rid of Computer Viruses Computer viruses are a major threat these days! How to get rid of computer viruses is what we will be discussing in this article.
Computers have become almost indispensable today. But a computer is after all a machine and it too needs care to remain functional all the time. So wherever Internet technology comes into picture, computer security is a subject of major concern. Read ahead to know how to get rid of computer viruses. Before we get cracking on how to get rid of computer viruses, let's understand what is a computer virus after all? Computer viruses are malicious programs that start operating anonymously from any location in your system. Like biological viruses, they also replicate themselves and spread from one workstation to another in a network. They are primarily responsible for sudden deletion and corruption of files. Besides, they hamper the security of important documents stored in your system and crash your system's RAM (Random Access Memory). But then how do you come to know about computer virus symptoms? Signs such as an extremely slow system, abrupt reboots, blue error screens, a lot of undefined and random errors and a large number of pop up windows opening simultaneously indicate a possible virus or a spyware attack! There are different types of computer viruses such as spyware, adwares, Trojan horses, web bugs and worms which also harm your computer. They self infest without the knowledge of your system and corrupt its sensitive data.
.. Question: How does a computer get infected with a virus or spyware?
Answer: There are literally dozens of different ways a computer can become infected with spyware, viruses, and other malware. Below is a l ist of the most common ways a computer can contract these infections listed in the order we believe are most commonly done.
All people who use the computer should be aware of how to properly use the computer and protect it from malicious software. Accepting without reading By far one of the most common ways a computer becomes infected is the user simply accepts what he or she sees on the screen without reading the prompt and/or understand what it's asking. Some common examples: 1.
While browsing the Internet, an Internet advertisement or window appears that says your computer is infected and/or that a unique plug-in is required. Without fully understanding what it is you're getting, you accept the prompt.
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When installing or updating a program, you're prompted (often checkboxes already checked) if it's ok to install additional programs that you may not want or are designed to monitor your usage of the program.
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