Computer security firm Prevx caused a bit of a stir last week when it blamed a recent Windows 7 problem—dubbed “The Black Screen of Death”—on a registry change the company attributed to Microsoft’s own November security updates. Now Microsoft is fighting back, and while it doesn’t actually say it knows what’s causing the problem, it seems confident in saying the security updates aren’t responsible.
“We’ve conducted a comprehensive review of the November Security Updates, the Windows Malicious Software Removal Tool, and the non-security updates we released through Windows Update in November,” the company wrote in its Microsoft Security Response Center blog. “That investigation has shown that none of these updates make any changes to the permissions in the registry. Thus, we don’t believe the updates are related to the ‘black screen’ behavior described in these reports.”
Prevx has since retracted their claim Microsoft’s security updates are responsible for the problem.
When the problem manifests, users see a completely black screen on login in to Windows 7. Some reports have the problem also impacting users of Windows Vista and Windows XP. As of now, Microsoft characterizes the problem as only impacting a limited number of Windows users, and notes that similar “black screen” behaviors are known to be caused by particular families of malware.