Viruses are malicious scripts which can spread by itself and causes harmful effects on the computer. They get into the computer from a removable media, Internet, e-mail, disk sharing etc. the precautions to be taken to protect the computer from virus are,

1. Careful when using the disks and files you get from other people.
2. Do not reuse the disks which have been in other computers.
3. Do not download files from insecure sites and do not open e-mail and attachments from strangers. Be cautious about the messages and e-mail even from the people you know with vague subject lines and contents.
4. Keep good anti virus software installed on the system and update it often. Keep the windows firewall turned on.
5. Never open attachments that end with .vbs or .js since these extensions are not used by a typical user.
6. Careful even when handling attachments with common extensions like .doc, .exe, .com, .xls or .ppt.

If at all we take these preventive steps there are chances that the system gets a virus. Now the aim is to clean the virus. If your system gets infected,

Step1. Visit the Antivirus software manufactures website, install the latest updates and scan again to identify the virus.

Step2. Let the antivirus software clean the virus automatically or quarantine it.

Step3. If the software fails to clean the virus then search the web to find a solution by typing the virus’ name for example. ‘BubbleBoy virus’. Download any software patch which can fix the infection or follow the available instructions to clean the virus manually.

Step4. Run another antivirus software scan to confirm that cleaned successfully.