The glitch apparently affects only Office 2000 users who don't have administrative rights on their computer, a Microsoft representative said Thursday.
"They are experiencing unexpected registration prompts, but it doesn't interfere with product functionality," he said.
Administrative rights allow a PC user to exercise total control over the computer's data. Giving such rights to nontechnical employees is considered by many security experts to be an unacceptable risk for companies. Thus, the glitch effectively hurts some companies that have implemented a good security policy.
Windows 2000 allows PC users to have one of several different levels of access to a computer: administrator, power user, limited and guest. Windows XP allows users to be assigned to the standard group with administrator privileges, a restricted group that has more limited privileges, or a custom group set up by the network administrator.
For PC users who don't have administrative rights, the glitch can be a pain. Every time customers start up Office 2000, the application will ask them to register again.
One U.K. company's help desk was swamped by people worried about the registration message, according to an employee who asked that his name not be used. "I notice that Microsoft is being very quiet about this. (There's) nothing on any of their Web pages that I can find."
The issue may have been caused by a recent patch. If so, it's not the first time that a software fix has gone awry. Last month, Microsoft's patch for a Windows 2000 flaw. Security and reliability are , an effort to raise the level of program quality in the software giant's popular applications.
Microsoft's representative didn't know if the cause of the problem had been determined but said that the software company is working on fixing the issue.
"We know who it affects. We know what happens. But we are working to assess what the problem is," the representative said.