题目内容：
How to protect your computer from being attacked by a virus:Be sure to have a good antivirus program and update it regularly. You will also want to make sure that yourInternet browser and operating system have had all the necessary security patches (补丁) applied.
Then, you may think you have a virus, but how do you really tell? You scan your system for viruses with a software program. If you don't have antivirus software, you can purchase it online or you can use Panda Soft- ware's free Active Scan that will scan you computer and report on any infections.
If the virus scoff finds an infection, it will give you the name of the virus or viruses that you have contracted. If your computer is infected, 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 ofthe antivirus manufacturers's websites.
What should you do to protect your computer from a virus?
You must make sure that you have an____________________________
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