So what can you do when a disparaging comment shows up? Review sites such as Yelp and TripAdvisor have made it easier than ever for consumers to share their negative experiences. When a review is posted, you can't simply demand that it be removed. You can, however, be proactive and ask regular customers to join the discussion to bury bad news under a flood of good news.

A bad review also presents an opportunity to improve your business. "Most business owners turn defensive," Agranoff says. "But most review sites have a place where businesses can address negative comments and explain."

He points to the example of a restaurant that infuriated a customer by shrinking the size of its salads but keeping the same price. "She blasted the place online, saying she'd never come back," Agranoff says. "The owner got in touch with her, and they went back and forth a dozen times. He explained that the price of produce went up, and eventually he apologized and changed the menu so the salad size would go back to what it had been, for a dollar more. She was so impressed that she took it upon herself to post positive reviews about the restaurant on other sites."

Online naysayers might be bitter former employees or demanding customers with unreasonable expectations, but many are people who have had disappointing experiences. If you make a good-faith effort to address their complaints, they might post a positive follow-up review or even remove their original attack.

No matter what your online strategy, be realistic: You can't control every single thing that's being said about you. Repairing an online reputation takes months, not days. The Internet has been a huge boom to countless small businesses. Unfortunately, monitoring your virtual image is the price you pay for it.

-- Reported by Elizabeth Blackwell in Chicago.
Elizabeth Blackwell is a freelance writer based in Chicago. She is the author of Frommer's Chicago guidebook, and writes for the Wall Street Journal, Chicago, and other national magazines.

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