The problem has been dubbed the 'black screen of death' because those affected are left with a black desktop and little else on their screen.
"Microsoft is investigating reports that its latest release of security updates is resulting in system issues for some customers," the software maker said in a statement. "Once we complete our investigation, we will provide detailed guidance on how to prevent or address these issues."
The issue was noted by British security firm Prevx on its blog on Friday, with that company also offering a suggested fix for the problem.
For more, read "Microsoft investigating 'black screen of death'" at CNET News.