Best Practices for Avoiding Viruses

Follow these best practices to avoid infecting computers with viruses:

Install on your system at least one commercial virus-detection program and use it regularly to check your computers for viruses. Be sure to regularly update the virus signature files. After you install an antivirus program, immediately update the virus signature files from the software manufacturer's Internet site. Check with the software manufacturer's documentation for specific instructions.

It is extremely important that you regularly update your antivirus program. In most cases, antivirus programs are unable to reliably detect and clean viruses of which they are unaware. Most commercial antivirus software manufacturers offer frequent updates. Take advantage of the latest download to ensure that your system is protected with the latest virus defenses.

Before you install Windows XP in a multiple-boot configuration, scan the other operating systems for viruses.

Back up files nightly or as needed so that damage is minimized if a virus attack does occur.

Before opening a file from a floppy disk or before starting a computer from a floppy disk, scan the floppy disk for viruses.

Do not open e-mail attachments from unknown senders. Delete the e-mail and attachments immediately.

When you receive an unexpected e-mail attachment from someone you know, verify that the sender intended to send you the attachment. Simply scanning the attachment for viruses is not sufficient because a new virus can propagate without the sender's knowledge. A virus scanner that does not know about the new virus might not catch the virus.

If the sender did not intend to send you the attachment, permanently delete it from the hard disk by selecting the attachment, holding down the SHIFT key, and then pressing the DELETE key. You must also delete the message from your e-mail program.

Never run a file that has a .vbs or .js file name extension unless you know exactly what it is going to do before you run it.

Regularly check the Microsoft Windows Update Web site and the Microsoft Office Update Web site for patches that fix vulnerabilities and provide security enhancements. In addition, independent software vendors (ISVs) might also provide security-related patches for other programs installed on the computer.

Configure the security settings in Microsoft Internet Explorer to protect against downloading infected files or malicious scripts. For more information about protecting computers from unsafe software, see Internet Explorer Help.

Do not allow users to log on as members of the Administrators group on their own computers because viruses can do more damage if activated from an account with Administrator permissions. Allow users to log on as members of the Users group so that they have only the permissions that are necessary to perform their tasks.

Configure Windows Explorer and My Computer to show extensions for known file types, show hidden files and folders, and show protected operating system files. For example, a malicious file with the name Report.doc.vbs appears in Windows Explorer and My Computer as Report.doc unless you deselect the option to hide extensions for known file types. To change these settings, in My Computer, click the Tools menu, click Folder Options, and then click the View tab.