Fires, hurricanes, floods: Business-interruption insurance protects against such calamities. But are you covered if your Internet service pro-vider goes bust?

In a word, no. And that's a problem. Last month, the failure of NorthPoint Communications (NPNT ) left thousands of small businesses with no Web access. "They pulled the plug with no warning," says David Rossi, a Foster City (Calif.) accountant who was offline for two days.

Rossi didn't have a business-interruption policy--not that it would have done him much good. While a few insurers, such as Chubb Corp. (CB ) and Marsh & McLennan (MMC ), cover temporary disruptions in service, none covers losses when an ISP shuts down. With more providers likely to fail, your best policy may be to line up a backup carrier now.

By Naween Mangi

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