Internet Security

Protect yourself... from viruses

What is a virus?

A virus is a small program designed by a person with malicious intent. It installs itself on your computer without your knowledge when you download files from the Web or in email or when you exchange files using a medium such as a USB key.

The virus then quickly spreads and tries to infect everything it can. It can take the form of a simple hoax message that displays on your screen or it can go so far as delete all of the content on your hard disk.

If your computer is infected by a virus, it might act strangely:

• Your computer runs more slowly than normal.
• Your computer stops responding and locks up often.
• Your computer crashes and restarts every few minutes.
• Your computer restarts on its own and then fails to run normally.
• Applications on your computer don't work correctly.
• Disks or disk drives are inaccessible.
• You can't print correctly.
• You see unusual error messages.
• You see distorted menus and dialog boxes.

These are common signs of infection but they might also indicate hardware or software problems that have nothing to do with a virus. There is no way to be certain if your computer is infected with a virus or not unless you run a scan of your hard disk with antivirus software that can remove the virus (source: Microsoft website).

There are various types of viruses. Here are a few examples:

• Boot Sector viruses: This type of virus installs itself in the boot sector of a hard disk and opens before any other applications.
• Program viruses: This type of virus installs on a particular application and opens before the application does.
• Macro viruses: This type of virus inserts itself into a Word, Excel or PowerPoint document and runs automatically as a macro (series of preset commands). It is the most popular because it is easy to program and easy to transmit because these applications are so widely used.
• Polymorphic viruses: This virus changes form every time it infects a new file making it difficult to detect.

How to protect yourself

Many forms of complex and hard-to-detect viruses exist and new viruses are appearing every day. Your computer should be protected at all times by good antivirus software, such as that included with NorthernTel's Internet Security Services:

The antivirus software included with NorthernTel's Internet Security Services:

• detects whether your computer is already contaminated with viruses and disinfects it;
• protects your computer from new incoming viruses in e-mail attachments or file downloads;
• automatically downloads and updates new virus definitions;
• lets you manually activate a scan on your computer to disinfect it

Virus security tips

Your antivirus software will do most of the work protecting you against viruses, but you can also reduce your risks by following these few tips:

• Never open (or even read) e-mail from an unknown source. Add it to your junk e-mail list.
• If you accidentally open junk e-mail, do not click on any links, reply to the message or download the attachment(s).
• If you are in doubt as to the source of an e-mail message but still want to open the attachment, scan the attachment with antivirus software before opening it. Delete any questionable files or e-mail rather than infect your computer. If you know the person who sent you the infected message, send him a new message (do not reply to his e-mail message) to notify him that his e-mail contained a virus.
• Don't use a USB key if you don't know where it came from. Many viruses can be transmitted in this manner.
• Regularly back up the contents of your hard disk. Perform a full scan of your hard disk with your antivirus software to disinfect it before you back it up.
• Make sure you have a backup of your operating system on CD-ROM so that you can reboot your computer in case of problems.
• Get NorthernTel's Internet Security Services which includes very efficient antivirus software.