Latest Windows patch may cause black screen for some users

The latest Microsoft Windows patches in November have been known to cause some black screens on users screens according to ComputerWorld, without a remedy to fix the problem.

The problem affects Microsoft products including Windows 7, Vista and XP operating systems, said Mel Morris , the CEO and CTO for the U.K. security company Prevx. Prevx was alerted to the problem by users of its security software last week, Morris said. Microsoft apparently made changes to the Access Control List (ACL), a list of permissions for a logged-on user. The ACL interacts with registry keys, creating visible desktop features such as a sidebar. However, the latest patches appear to make some changes to those registry keys. The effect is that some installed applications aren't aware of the changes and don't run properly, causing a black screen, Morris said.