Within minutes, Windows 7 users who have experienced those problems disagreed, calling the explanation "hand washing" and noting that if the company's conclusion was correct, then many affected users must be "under some sort of bizarre bad battery curse."
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According to Stephen Sinofsky, the president of the Windows division, Windows 7 is doing what it's supposed to when it reports that a laptop battery needs to be replaced, one of the symptoms that users began reporting as long ago as June 2009.
"To the very best of the collective ecosystem knowledge, Windows 7 is correctly warning batteries that are in fact failing," said Sinofsky in an entry to the Engineering Windows 7 blog Monday afternoon. "In every case we have been able to identify the battery being reported on was in fact in need of recommended replacement."
Sinofsky also dismissed claims by a minority of users that Windows 7 had permanently crippled their notebooks' batteries. Numerous users said that after upgrading to Windows 7, their batteries' lifespan was dramatically shortened, then completely curtailed. Returning to another operating system, even Linux , did not restore the battery's performance.
"Windows 7 is neither incorrectly reporting on battery status nor in any way whatsoever causing batteries to reach this state," Sinofsky maintained. He also said that it was impossible for Windows 7 to harm the battery because of the way the operating system interacts with the hardware.
"There is no way for Windows 7 or any other OS to write, set or configure battery status information," Sinofsky said. "All of the battery actions of charging and discharging are completely controlled by the battery hardware. Some reports erroneously claimed Windows was modifying this information, which is definitely not possible."
But one battery maker said it was possible that Windows 7 was involved in some way. "The operating system usually receives information from system firmware which is responsible for monitoring battery capacity and operation," said a spokeswoman for Boston-Power, a Westborough, Mass.-based company that makes long-life Lithium-ion batteries. The firmware she referred to is the PC's BIOS, which boots the computer and initializes the hardware components.
"If there is an issue with the passing of information between the firmware and the operating system, it might cause improper warnings issued by the OS," she added.