It's every PC user's worst nightmare. One minute you're innocently checking your email, editing a report and reviewing documents—then all the sudden your screen goes blank. Panic ensues as you realize your computer may have caught a virus and all of your important files could conceivably be wiped out.

One Washington man says the software maker Symantec Corp. unfairly capitalizes on this fear among PC users. Yesterday, he filed a lawsuit against the company, claiming it persuades consumers to buy its products by frightening them with misleading information about their computers' health.

The lawsuit, which seeks class action status, alleges that Symantec distributes trial versions of its scanning software to consumers, and when they run the products on their computers, they receive fraudulent messages that their PCs are plagued with privacy risks, errors and other serious problems.

The plaintiff claims Symantec's scanning software is a ploy to market Norton Utilities, PC Tools Registry Mechanic and PC Tools Performance Toolkit, which the company claims help improve PC performance and privacy. Furthermore, he likens the company's products to “scareware,” or malicious software that causes pop-up messages to appear on users' computers informing them that their PCs are infected with viruses.

Read Thomson Reuters for more information about the lawsuit.