David Kennerley said in a post on the Prevx' blog that patches released as part of the November patch cycle from Microsoft caused machines to display a black screen. He claimed that this was the case because the patches in question made changes to the access control lists of certain parts of the registry. More specifically, the
HKEY_LOCAL_MACHINESoftwareMicrosoftWindows NTCurrentVersionWinlogonShell key.
Conveniently, the antivirus vendor also provided a free fix for the problem, which should've probably raised some red flags in the media. Microsoft delved into the issue, and after studying the patches in question came to the conclusion that they do not touch the registry at all.
"Microsoft has investigated reports that its November security updates made changes to permissions in the registry that that are resulting in system issues for some customers," said Christopher Budd, Microsoft's security response communications lead, in an e-mailed statement to InformationWeek, "The company has found those reports to be inaccurate and our comprehensive investigation has shown that none of the recently released updates are related to the behavior described in the reports. While we were not contacted by the organization [that] originally made these reports, we have proactively contacted them with our findings."
In addition, Microsoft checked with its worldwide Customer Service and Support organisation, which found that the black screen issue was not "a broad customer issue". Since Microsoft was not contacted about any problems, they have no idea what's causing the black screen - but they do state that malware in the Daonol family is known to cause black screens.
This further solidifies my belief that you should always take the statements from security vendors with heaps of salt. Remember, these guys have a product to sell, and they rely on fear. They need to seed it, so they can sow it later on.
Just use a modern Windows system (Vista or 7), and install Microsoft Security Essentials, a minimalist, fast, and efficient anti-malware and antivirus program, and you're pretty much okay. If security is paramount to your computer's operation, stick to Mac OS X, Linux, BSD, or Solaris.