12 Tips to Maintain a Virus Free Computer

Is your computer infected with virus? Do you often get mysterious error messages? Well this is a common problem faced by almost all the computer users across the globe. There are many viruses and worms out there that could infect your computer. Some are harmless, but, they do have the capacity to do any number of nasty things, up to and including, erasing all data from your computer. However there are ways to keep viruses away from your PC. Here are the 12 tips to maintain a virus free computer.

1. Email is one of the common ways by which your computer can catch a virus. So it is always recommended to stay away from SPAM. Open only those emails that has it’s origin from a trusted source such as those which comes from your contact list. If you are using your own private email host (other than gmail, yahoo, hotmail etc.) then it is highly recommended that you use a good anti-spam software. And finally NEVER click on any links in the emails that comes from untrusted sources.

2. USB thumb/pen drives is another common way by which viruses spread rapidly. So it is always a good habit to perform a virus scan before copying any data onto your computer. NEVER double-click the pen drive to open it. Instead right-click on it and select the option “open”. This is a safe way to open a pen drive.

3. Be careful about using MS Outlook. Outlook is more susceptible to worms than other e-mail programs, unless you have efficient Anti-Virus programs running. Use Pegasus or Thunderbird (by Mozilla), or a web-based program such as Hotmail or Yahoo (In Firefox).

4. As we all know, Internet is the main source of all the malicious programs including viruses, worms, trojans etc. In fact Internet contributes to virus infection by up to 80%. So here are the tips for safe surfing habits so that you can ward off virus infection up to the maximum extent.

• Don’t click on pop-up windows that announce a sudden disaster in your city or announce that you’ve won an hourly prize. They are the ways to mislead Internet users and you should never trust them.
• You can also use a pop-up blocker to automatically block those pop-ups.

5. Most of us use search engines like Google to find what we are looking for. It is quite obvious for a malicious website to get listed in the search results. So to avoid visiting those untrusted malicious websites, you can download and install the AVG LinkScanner which is a freeware. This tool can become very handy and will help you to stay away from malicious websites.

6. Install a good antivirus software and keep it updated. Also perform full system scan periodically. It is highly recommended that you turn on the automatic update feature. This is the most essential task to protect your PC from virues. If PC security is your first option then it is recommended that you go for a shareware antivirus software over the free ones. Most of the antivirus supports the Auto-Protect feature that provides realtime security for your PC. Make sure that this feature is turned on.

7. Install a good Antispyware program, that operates against Internet malware and spyware.

8. Never open any email attachments that come from untrusted sources. If it is a picture, text or sound file (these attachments end in the extensions .txt, .jpeg, .gif, .bmp, .tif, .mp3, .htm, .html, and .avi), you are probably safe, but still do a scan before opening.

9. Do not use disks that other people gave you, even from work. The disk could be infected with a virus. Of course, you can run a virus scan on it first to check it out.

10. Set up your Windows Update to automatically download patches and upgrades. This will allow your computer to automatically download any updates to both the operating system and Internet Explorer. These updates fix security holes in both pieces of software.

11. While you download files from untrusted websites/sources such as torrents, warez etc. make sure that you run a virus scan before executing them.

12. And finally it is recommended not to visit the websites that feature illegal/unwanted stuffs such as cracks, serials, warez etc. since they contribute much in spreading of viruses and other malicious programs.

A Virus Program to Disable USB Ports

In this post I will show how to create a simple virus that disables/blocks the USB ports on the computer (PC). As usual I use my favorite C programming language to create this virus. Anyone with a basic knowledge of C language should be able to understand the working of this virus program.

Once this virus is executed it will immediately disable all the USB ports on the computer. As a result the you’ll will not be able to use your pen drive or any other USB peripheral on the computer. The source code for this virus is available for download. You can test this virus on your own computer without any worries since I have also given a program to re-enable all the USB ports.

1. Download the USB_Block.rar file on to your computer.

2. It contains the following 4 files.

• block_usb.c (source code)
• unblock_usb.c (source code)

3. You need to compile them before you can run it. A step-by-step procedure to compile C programs is given in my post - How to Compile C Programs.

3. Upon compilation of block_usb.c you get block_usb.exe which is a simple virus that will block (disable) all the USB ports on the computer upon execution (double click).

4. To test this virus, just run the block_usb.exe file and insert a USB pen drive (thumb drive). Now you can see that your pen drive will never get detected. To re-enable the USB ports just run the unblock_usb.exe (you need to compile unblock_usb.c) file. Now insert the pen drive and it should get detected.

5. You can also change the icon of this file to make it look like a legitimate program. For more details on this refer my post – How to Change the ICON of an EXE file (This step is also optional).

I hope you like this post. Please pass your comments.