Technology giant Microsoft has negated all speculations that were linking the issue in its Windows operating system, known as the "Black Screen of Death", to the firm's latest security update, and said that it is most likely a case of malware.

Some users of Windows, after they log on to their machines, end up being greeted by a completely blank screen, and many at first had linked it to the company's November 10 security update, which has now been discontinued. Experts are now linking the problem, which is also affecting systems running on Windows XP and Vista, to malware.

In a post on the company's official security site, Microsoft has shared that an investigation that the firm had undertaken "found that our November Security Updates are not making changes to the system that these reports say are responsible for these issues", further hinting that the unusual behavior's root cause is most probably a malware, like Daonol.

The blame was put on November's update by software firm Prevx, which has now apologized to Microsoft "for any inconvenience that the earlier claims may have caused".

The firm has officially announced that the blank screen problem affects the company's Windows 7, Vista, XP, NT, and Windows 2000 editions and users who are experiencing the phenomenon have been directed to contact Microsoft's customer service line.