The broader Genuine Software Initiative will include a similar campaign, built around a tool called Office Genuine Advantage, to fight piracy of Microsoft's dominant desktop applications suite. Microsoft began testing OGA in April and said last week that the company is "absolutely committed" to going forward with the software, although it wouldn't elaborate on when the tool will be officially released.

WGA, which began an escalated rollout in April, has been criticized as spyware for stealthily installing itself on PCs, sending information back to Microsoft and nagging users who refused to install the tool. The software vendor turned off most of those features in late June.

Reports of WGA falsely crying wolf about legitimate copies of Windows XP have also abounded. Most of the people claiming to be victims have been gamers or PC hobbyists who had upgraded their hardware. But some have been businesses, such as S&S Cycle Inc., a maker of motorcycle racing parts in Viola, Wis.

Because WGA failed to recognize the company's 180 PCs as legal, it rescanned them every morning and sent back so much data to Microsoft that "our network came to a screeching halt," said S&S network administrator Karen Zander. She eventually fixed the problem by working with Microsoft technical support.

Microsoft responded to the criticisms last week by releasing statistics about WGA's purported effectiveness via blog postings by Alex Kochis, a licensing manager on the WGA team. Kochis claimed that only "a fraction of a percent" of the 60 million or so PCs that have been reported by WGA thus far were running legitimately licensed copies of Windows XP.