The company is also reminding consumers to carefully vet their software purchases, particularly if they're bargain hunting.

"The whole 'Blue Edition' software is a fabricated claim by pirates made up out of whole cloth, in order to deceive consumers into buying this low-quality counterfeit software," said Matt Lundy, a senior Microsoft attorney focused on anti-piracy efforts.

"Consumers need to arm themselves with information so that what seems to be a bargain on software doesn't turn out to be a counterfeit ... with malware attached that causes your computer to irreversibly crash six months from now," he said. Microsoft offers www.howtotell.com as a resource to help people track piracy and counterfeiting information.

The pirates marketing message is usually a variation on the following (hogwash):

"There's quite a big chance that you've never heard of this 'Blue Edition', because - it is only available to equipment manufacturers and not to the general public. This is the copy from the original disk, which is (as said before) only accessible to technicians of Microsoft.

"This version of Microsoft Office 2007 will never appear for sale, since this is the only version where there is no need for a serial. This version also doesn't need an activation."

Microsoft became aware of the scheme several months ago, Lundy said. It represents a new tactic for pirates who in the past have concentrated on high-quality forgeries designed to reproduce the look and feel of genuine Microsoft software, including holograms and other security features.

"They're enticing the sale through this claim that it's part of a marketing overrun because the pirates recognize they can't convince people that it looks like the genuine Microsoft product," he said. "So they try to create this elaborate scheme to fool people into thinking they're getting a special deal or a break because of an overrun."

"We received a number of complaints from consumers about their purchase of Blue Edition," Lundy said.

Microsoft is monitoring online auction sites and has removed auctions from hundreds of sellers, primarily in North America, peddling the bogus goods. As a last resort, he said, Microsoft files lawsuits as it's doing today.

"The number of online marketplaces that pirates are using and abusing are increasing. The area of reach of pirates from all over the world is increasing. The types of schemes that are out there are increasing," he said.

The lawsuits Microsoft is filing cover 63 cases in 12 countries and touch 21 online market sites, including major brands like Amazon and eBay:

www.amazon.com, www.anywherepc.com, www.cheapestsoftwareanywhere.com, www.computerdoctorofmiami.com, www.computerrepairportal.com, www.craigslist.org, www.crossloop.com, www.eBay.com, www.ebid.net, www.elitestores.net, www.insiderpages.com, www.ioffer.com, www.laptopsandmoreinc.com, www.myspace.com, www.NextTag.com, www.pcworld.com, www.Pricegrabber.com, www.sell.com, www.shopmsn.com, www.superpages.com, and www.ubid.com.

"We hold pirates responsible for piracy," Lundy said, not the auction sites.