In a move that could rankle privacy advocates, Microsoft said Monday that it is adding the PC equivalent of a flight data recorder to the next version of Windows, in an effort to better understand and prevent computer crashes.

The tool will build on the existing Watson error-reporting tool in Windows but will provide Microsoft with much deeper information, including what programs were running at the time of the error and even the contents of documents that were being created. Businesses will also choose whether they want their own technology managers to receive such data when an employee's machine crashes. "Think of it as a flight data recorder, so that any time there's a problem, that 'black box' is there helping us work together and diagnose what's going on," Microsoft Chairman Bill Gates said during a speech at the Windows Hardware Engineering Conference here. For consumers, the choice of whether to send the data, and how much information to share, will be up to the individual. Though the details are being finalized, Windows lead product manager Greg Sullivan said users will be prompted with a message indicating the information to be sent and giving them an option to alter it, such as removing the contents of the e-mail they were writing when the machine crashed. Also, such reporting will also be anonymous.