If you want to use this special software you need to download it and install it in your system. Then it will scan your computer.

Depending upon your needs you can opt for a full scan or a quick scan. If you opt for a full scan then the software will scan for viruses, check hard disk performance, and network safety

The quick scan will only scan for viruses only in specific areas in your computer. Naturally the full scan is slower than the quick scan

You also get a virus database, information about online threats and general computer security documentation and tools from this service.

Microsoft has such a service. It is called Windows Live One Care Safety Scanner. This service is offered free for now. However Microsoft intends to charge a fee for the last few mentioned services.

Other soft wares that do this service are Trend Micro from House calls, and Symantec security check from Symantec.

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