You’re probably down on your computer luck, and you may have been lax about keeping up those healthy computer habits. I don’t want to sound like I am suggesting you close the door now that the cow is out of the barn, but any advice on viruses really needs to start with one thing: prevention.

Be sure to have a good antivirus program and update it regularly. You will also want to make sure that your Internet browser and operating system have had all the necessary security patches applied.

Prevention is the name of the virus game, and you do need to make friends with a good antivirus program.

Now back to the information for you unlucky, unhappy readers who may have contracted a virus. You may be asking, “Is it really a virus?”

First, you may think you have a virus, but how can you really tell?

Viruses often cause erratic behavior, smiley faces may pop up, your screen may disappear, or your computer may crash.

The trigger that activates the virus can be almost anything. For instance, the virus can be activated the minute it is installed. Or it may start its dirty work the next time you start your computer.

In many cases, a virus can reside inside your computer in an inactive state, waiting for a certain event (such as a certain date) to happen.

From the moment the virus infiltrated your computer to the time that it made itself known to you, you could have innocently spread the virus to others. A very disconcerting sign that you have a virus is when friends call or e-mail to let you know you have sent them a virus-infested e-mail.

Scan Is Necessary

So you suspect you have a virus. How can you find out for sure?

You scan your system for viruses with a software program. If you already own an antivirus program and your computer is operable, you can start your antivirus program and initiate a scan of your entire computer.

However, chances are if you contracted a virus, the virus definitions that your program is using are out-of-date. So first, visit the Web site of your antivirus manufacturer and update your antivirus software by downloading the latest definitions.

If you don’t have antivirus software, you can purchase it online or you can use a free online scanning tool. Two of the best are Panda Software’s free ActiveScan at www.pandasoft ware.com and McAfee’s Free Scan at http://us.mcafee. com/root/mfs/default.asp. These programs will scan your computer and report any infections.

Manufacturer’s Web Site

If the virus scan finds an infection, it will give you the name of the virus or viruses that you have contracted.

If your computer is contaminated, you need to take immediate action.

Depending on the severity of the virus, the health of your computer, as well as the security of your computer data, may be at risk.

Look up the virus at one of the antivirus manufacturers’ Web sites.

McAfee (www.mcafee. com), Panda Software (www.panda software.com), and Symantec (www.symantec.com) are all informative sites.

Sometimes the manufacturers will have a software program that you can download for the removal of the virus. Removal instruction may be offered as well.

Viruses vary in severity. Some are easy to eliminate and repair. Others can be very nasty and repairing their damage could involve some complex reprogramming.

If your good computer luck has returned, you may be able to remove the virus yourself. If, however, you have contracted an invasive virus, don’t hesitate to leave the work to a local computer professional.

The last thing to remember is to develop healthy computer habits. Remember, an ounce of prevention is worth a pound of cure.

Be sure you have a good antivirus program installed on your computer and update it regularly.