Computer Virus And Internet Worms Explained

Is your computer sluggish? It won’t open programs and you can’t get into anything? Well, maybe you have a sick computer. Just as people get ill from viruses, so do computers. When this happens, you need to have a computer technician look at the computer to re-format and get rid of the virus. If you know something about computers, you might be able to do this yourself.

What is a Virus?

A virus is a parasitic program written to intentionally enter a computer without the user’s permission or knowledge. The word parasitic is used because a virus attaches to files or boot sectors and replicates itself, which allows it to spread. Though some viruses do little more than copy themselves, others can cause serious damage or affect program and system performance. A virus should never be assumed harmless or left on a system.

Types of viruses

Viruses are classified by the ways they infect computer systems:

1) Program: Executable program files such as those ending with the extensions .Com, .Exe, .Ovl, .Drv, .Sys, .Bin
2) Boot: Boot Record, Master Boot, FAT and Partition Table.
3) Multipartite: Both program and boot infector.

What is Trojan Horse?

Besides being a large wooden horse used in the Trojan war 2500 years ago (and more recently by Brad Pitt), a Trojan Horse or Trojan is a computer program that seems innocuous or harmless, but conceals another more nasty function. Generally a Trojan is contained in a part of program brought into your computer from an outside source – (e.g. floppy disk, CD, internet download, infected email). Trojans can be dangerous sometimes. For example a program may appear to be a computer game demo, but while you enjoy the game, it may be happily formatting your hard disk or emailing porn sites to everyone in your email address book.

Trojans are also used as a ‘back door’ or ‘trap door’ to sneak into a computer’s operating system’s information. An example is a program that pretends to be the system log-in program (such as you find in Windows NT/XP or Linux). When an unsuspecting user tries to log-in, the Trojan program captures the user-name & password. Then it may indicate a failed log-in attempt and exit to the real log-in program. The user may successfully log into the system next time, but by that time Trojan has also got enough details to log into the system.

Example Trojans

Notroj. This Trojan horse pretends to be a program that guards against Trojans. It’s actually a time bomb that wipes out the hard disk after it’s more than 70 percent full.

PWSteal.Refest A Trojan Horse that installs itself as a BHO (Browser Helper Object) for Internet Explorer and steals online banking information when it is submitted in web forms.

PWSteal.Likmet.A A Trojan horse that displays a fake MSN Messenger logon window and steals the password provided.

Run.me. This is a graphics program, which plays the Star Spangled Banner and displays the American Flag while it worms its way into the hard disk and erases the data on it.

What is Worm?

A Worm is a self-propagating program that works its way through a system or network (like the Internet), often causing damage. It does not require a host program to activate it. Someone has to insert a worm directly into network of interconnected computers where messages can be sent from one to another and data files and programs exchanged. An example is a local area network where each computer has its own files, programs operating systems and hard discs such as would be found in a university or corporate setting.

Example Worms

Alarm Clock Worm. A worm that reaches out through the network to an outgoing terminal (one equipped with a modem), and places wake-up calls to a list of users.

Worm Watcher. A special program which automatically takes steps to limit the size of a worm, or shut it down, it grows beyond a certain limit. The worm watcher also maintains a running log recording changes.

Computer Fits? You Need Registry Repair

Is your computer getting slower and slower? Is this occurring despite not using any more memory? Are you having frequent freezing or spontaneous shutdowns? You may have tried erasing all the programs that you don’t use with no success. You may even have tried anti virus software thinking that you had been infected by a virus, and were disappointed to find that this didn’t improve things.

Well I have good news for you and bad news. The good news is that your problem is common and repairable, and also that you were on the right track. The bad news is that you are probably suffering from the symptoms of a virus infection and that you probably need to get a tool that will clean your registry which is yet another cost incurred.

A computer registry is the part of your operating system that monitors and records the information for all the settings and preferences of the users for all hardware and software. Whenever a change is made it is recorded in the registry. As such it becomes cluttered and congested with time. The registry can also be manipulated with virus code to give up sensitive information and to cause malfunctions in the operating system. Just like any tool you use your computer needs regular maintenance and repair including a good thorough registry repair.

You need to be careful though when you select a registry repair tool as there are many out there with varying levels of effectiveness and related risk. You see it is possible to make changes in the registry that are irreversible and can forever affect negatively the proper performance of your computer. So how can you make a good informed decision?

Well there are several publications dealing with computer technology that will regularly review products such as registry repair software and give feedback on the pros and cons of each product. You need to pick one that is on the mainstream market for sure as they have had the most thorough testing and review and generally come from the most trusted sources. Also pay attention to the banter on the net. There are several forums that you can go to to ask questions and get feedback from actual users like you who have used the software themselves. This can be extremely helpful as long as you take all this advise with a grain of salt.

Be careful but also be excited because you will be amazed at the difference that a little maintenance registry clean will change the operating performance of your pc.

Cleaning Your Registry And Increasing Computer Speed

Registry cleaner is the software that cleans up the registry of a computer to optimize its performance and sped. Registry is the place on a computer where the vital data on its configuration and the installed programs are saved to enable the operating systems to make use of the same. It is an applet within the pack of the operating system. It keeps a log of the activities of the P.C. and can be well compared with a concurrently updated check list of the performance list of the system. In the normal usage of computer like addition or deletion of software, or installation of hardwires or if third party intrusion programs like spy ware or ad ware is running then your registry need to be repaired.

Registry cleaners are a must to protect your systems from malicious programs and harmful processes.
One has to be very careful in editing the registry and calls for basic computer awareness. The first and foremost precaution before any registry cleanup is to take a back up of the registry. This facility is supported by all registry cleaners. Negligence to clean up the registry where the system is severely affected by third party programs and consequent slowing down and related problems may reduce even the life of the computer. Hence it is imperative that you spend a few dollars and time on the registry cleaners to save you from future embarrassments. While most of us are familiar with the anti virus and anti spam firewalls etc perhaps due attention is not given for registry cleaners.

Registry cleaners helps run PCs at optimum efficiency as it takes care of the potential dangers caused by spyware adware etc. that runs in the background of computer and slow down the same besides monitoring your internet activity .Registry cleaners also fix the inherent problems of the systems . There are free registry cleaners available on net. However it is well advised to go for a priced professional program to have good technical support.

Cleaning and Organizing Your Computer

It is a good idea to think of your PC as an office. It stores files, programs, pictures. This can be compared to an actual office’s files, machines and decorations. The operating system is the boss. With this image in mind, think of an office you’ve visited that was slow and inefficient. There were probably many different reasons for the inefficiency. This is the same with a computer.  There can be many items that slow down your computer. Perhaps the one most commonly overlooked is disorganization and clutter.

Disk Cleanup

An office can accumulate a lot of unnecessary files, machines, and decorations. This is the same with your computer. One of the best ways to keep this clutter under control is to perform a cleaning utility periodically. In Windows this cleaning utility will be called a “disk cleanup.” It removes a variety of unnecessary files depending on the options you have selected.

To perform a disk cleanup on Windows XP you can simply click on “my computer” under the start menu. Than right click on your “c drive” or “hard disk” and choose properties.  Than click “disk cleanup” and follow the prompts. When selecting files to clean up, or delete, Windows will give you information to help you decide. When looking over the list of file types, you would simple click on the name of the file type and read the description placed below in the description area. This will let you know if the files can be safely deleted. To select the file group just check the box next to the group name. When finished selecting press “OK” to finish.

Now, performing a disk cleanup is not very time consuming, just a couple minutes, and it may save more time in the end by making your computer run faster. However, a disk cleanup should be run periodically rather than just once in a great while. One way to make this run periodically is to make it a scheduled task. This will allow your computer to run it automatically with intervals and time of day determined by you. Yet, you can always run it yourself periodically without creating a scheduled task.

Add or Remove Programs

The information given above can help you get rid of some unnecessary files, but you may also need to clean out some unnecessary programs as well. This can be done using the “add or remove programs” utility in Windows. This is located in the control panel and lists all of your currently installed programs along with an option to uninstall them. It is a good idea to browse through the add or remove programs utility every once in a while just to make sure that all programs are of usefulness.

If there are programs listed that are no longer used, you can simply highlight the program and click the uninstall button. Windows will than begin the process to uninstall the program. In most cases, to finish uninstalling a program, it is wise to restart your computer. This will dump and files that are held temporarily.

The add or remove programs utility is very useful, but not all of the programs are listed up front. Programs that come pre-installed on your computer and the Windows operating system can also be uninstalled. For instance, Outlook Express is a default e-mail program that comes with the Windows XP operating system. If you do not use this e-mail program you can uninstall it. Click “add or remove windows components” found in the add or remove programs utility and simply follow the instructions.

Defragment

Many offices contain a large number of files and programs that are valuable and cannot be thrown away. In fact, they may contain files that are not even used, but still have to be retained for some reason. Although these files must remain in the office, they need to be organized. This is why we create file folders that hold groups of files that are related. Than we store them in cabinets that are arranged in alphabetic order.

In a computer, the files that are saved are placed on the hard drive. However, they are placed according to the time that they were saved. So, if you open a word document and save the file as “file A” and than open another document and save it as “file B”, you have a “file A” placed next to “file B.” This is fine, but if you open “file A” later on and save it again, than the added information is saved next to “file B.”

When files are broken up this way it is referred to as a fragmented file. This means that the computer must find the first part of the file and then find the second part of the file to open that one word document. This can make your computer run slower. However, Windows has created a utility that is meant to rearrange files so that they are no longer fragmented but sit right next to each other.

You can run the disk defragmenter by selecting “all programs” under the start button. Next, select “accessories” and “system tools” and you will see “disk defragmenter.” In fact, this is also an alternative way to select the disk cleanup mentioned earlier. Before starting the defragmenter you can analyze your hard drive to see if Windows recommends performing the defragmenter. It will either say that you should or should not defragment at this time.

If you need to defragment your computer, simply hit the defragment button. It may take your computer a while to finish this task depending on the speed of your computer and the amount of defragmented files. It could take from about 15-30 minutes or more. However, you can still use the computer while the disk defragmenter is working.