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."
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.
Originally, Microsoft thought that very thing. Last Wednesday, when the company first responded to the growing chorus of complaints, it said, "We are investigating this issue in conjunction with our hardware partners, which appears to be related to system firmware (BIOS)."
Debugging battery-BIOS-operating system issues can be "very complicated," the Boston-Power spokeswoman said, because the BIOS can vary from one laptop make and model to another. "It is difficult to know what control the OS has over battery operation in specific systems," she admitted.
Sinofsky didn't dive into that level of detail in his blog entry, but emphatically laid out Microsoft's theory that users' reactions were due to the fact that the "Consider replacing your battery" notification was new to Windows 7. He also said Microsoft had traced each complaint, even of new notebooks behaving this way, and found that in all cases the battery really was kaput. Microsoft also combed through the Windows 7 code to verify that there was no way for the operating system to modify a battery's status information.
That didn't matter to users. In comments added to Sinofsky's blog, as well as in messages posted to the long support thread dedicated to Windows 7 battery issues, users rejected the executive's arguments.
"I completely reject Steven Sinofsky's explanation. It's simple hand-washing," said a user identified as "Btstech" on the support thread. "There are hundreds of postings here explaining the problem. Immediately after installing Windows 7, people's batteries are effectively 'dying.' Numerous people have purchased NEW batteries and encountered the same behavior immediately.
"The OS is causing this for some reason. Not saying it's damaging the batteries, but it's rendering them useless," Btstech continued. "This is a no brainer. There is a problem here with the new operating system and the way it interacts with various laptops and it must be fixed."
Another user took noted Windows blogger Rafael Rivera to task for his comments on the same thread. Rivera, who writes the Within Windows blog , had questioned comparisons of battery usage between Windows XP and Windows 7 because the latter's flashy Aero interface increases battery consumption.
"If what you are saying is true, then we simply have a different problem: Windows 7 provides dramatically worse battery life than any of the operating systems that preceded it," said "kev99sl" in reply to Rivera. "If this is not the case, and there is no actual problem at all, then a new battery should provide the cure, right? Ah, but new batteries don't solve the problem: the behavior is repeated. Well then, the new batteries must be defective, correct? Then it would seem that you would have all of us believe that we are suffering from an oddly focused, unusual affliction that will somehow not allow us to purchase properly functioning batteries, regardless of the maker. Apparently we're under some sort of bizarre bad battery curse."
In a comment added to Sinofsky's blog entry, the same user argued that the problem wasn't whether batteries were new or not, but that Windows 7 consumed power at a prodigious pace, a complaint that precedes the new operating system's release .
"At some point, Microsoft and its OEM partners are going to have to conclude that a random sampling of consumers are somehow experiencing the extraordinary bad luck of constantly purchasing faulty batteries or, more likely, that there is an issue," said "kev99sl" Monday. "I think it's simply a matter of time until the latter is uncovered, as the majority of impacted consumers are just now coming around to working through battery warranty issues, purchasing new batteries, returning new batteries assumed to be faulty, etc. only to discover that second and third newly purchased batteries do not rectify the problem."
Sinofsky denied that there was a problem with Windows 7, old batteries or new. "We have no confirmed cases of new machines with the as-purchased batteries," he said, contradicting numerous reports on the support thread. But Sinofsky also said Microsoft would continue to investigate a possible problem in the operating system. "We are going to continue to be diligent and use all the tools at our disposal to get to the bottom of a report that has the potential to require a code change we would distribute to customers," he acknowledged.
Microsoft is clearly concerned about the potential fallout over the battery reports if Sinofsky is turning his attention to it: Yesterday was the first time that he has posted to the Engineering Windows 7 blog since Aug. 10, 2009 , when he defended the company's reaction to a crash bug in the not-yet-released OS.
He also encouraged users with new batteries, or those thought to be in good condition, to contact him via the blog's e-mail form if they see the Windows 7 warning.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld . Follow Gregg on Twitter at @gkeizer or subscribe to Gregg's RSS feed . His e-mail address is email@example.com .
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This story, "Users Dispute Microsoft's Explanation of Windows 7 Battery Problems" was originally published by Computerworld.