Protecting against viruses and Trojan horses

In today's computing world, you must prevent intentional intrusions into your computer and network that take the form of viruses and Trojan horses. Follow these tips to help prevent virus outbreaks and Trojan horse attacks.

For users:

• Educate yourself about viruses and how they are commonly spread. You can unwittingly bring viruses into the network by loading a program from a source such as the Internet, online bulletin board, or e-mail attachments.
• Learn the common signs of viruses: unusual messages that appear on your screen, decreased system performance, missing data, and inability to access your hard drive. If you notice any of these problems on your computer, run your virus-detection software immediately to minimize the chances of losing data.
• Programs on floppy disks may also contain viruses. Scan all floppy disks before copying or opening files from them, or starting your computer from them.
• Have at least one commercial virus-detection program and use it regularly to check your computers for viruses. Be sure to obtain the latest virus signature files for your program when they are available, because new viruses are created every day.

For administrators:

• Before putting a new program on the network, install it on a computer not attached to the network, and then check it with your virus-detection software. (Although it's advisable to log on to your computer as a member of the Users group, you should install the program while logged on as a member of the local Administrators group because not all programs install successfully when installed by a member of the Users group.)
• 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. Users should log on as members of the Users group so that they will have only the permissions necessary to perform their tasks.
• Require users to create strong passwords so that viruses cannot easily guess passwords and obtain Administrator permissions. (You can set password requirements using the Group Policy snap-in.) For information about creating strong passwords, click Related Topics.
• Regularly back up files so that damage is minimized if a virus attack does occur.