Microsoft's program for testing whether a PC is running a genuine copy of Windows, WGA (Windows Genuine Advantage), has drawn considerable fire from users since it was launched last July.

This week Microsoft gave users another reason to complain when the company confirmed the version of the program it is delivering as a "high priority" automatic update for Windows PCs is a test version. Usually, Microsoft distributes test versions of software separately from updates and users are given the opportunity to sign up for the software before test versions are downloaded.

Microsoft said users can still opt out of downloading the update, called WGA Notifications, and that its user licence makes it clear it is prerelease software. However, many users don't read an entire licence agreement, which can be lengthy, before they download software to their computers. And some download all Windows updates without looking too hard at the fine print.

Microsoft has mounted an aggressive program to eliminate counterfeit and pirated versions of Windows, and WGA is a part of that. The program was first distributed not as an automatic update, but to users of Microsoft's download services who wanted to install add-on software, excluding security releases, for Windows. Since WGA's release, users have complained of bugs in the program.

One of those problems, in which the software identifies a genuine copy of Windows as pirated or counterfeit, apparently persists, according to comments sent by email to PC Advisor from one Windows user.

"I bought my PC with a legitimate XP licence, which I have registered, and now my machine keeps telling me I have pirated software," said Windows XP user Doug Fleming. "I paid good money for legitimate software and now my PC locks up whenever I get a message telling me my software isn't genuine. To make matters worse, there is no contact information to get the problem rectified."

According to Microsoft, validation failure is "almost always caused by the use of a non-genuine Windows licence". "In many cases, customers don't know they have received a counterfeit copy," the company said in a email statement through its public relations firm Waggener Edstrom.

Another Windows user said in an email that the WGA Notifications service, which has to send information about a user's PC over the internet back to Microsoft, could pose a security risk. Microsoft last week defended itself against charges that this aspect of the program was acting like spyware, which is software that gathers users' information through their internet connection without users' knowledge.

"The process seems to open a door for hackers to exploit," Windows user James Slotter said in an email. "It might also open a door for another vendor to provide a more secure set of programs than Microsoft is willing to provide."

"We understand customers’ concern about installing a program that could possibly impact their systems," Microsoft said in a statement through Waggener Edstrom. "WGA Notifications has gone through a thorough testing period. We are confident that the software can be installed and used safely."

WGA Notifications will be rolled out worldwide by the end of the year, Microsoft said.

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