A recent Vista update is causing headaches for users with USB devices.

Microsoft last week re-released a software update intended to provide performance and reliability enhancements for Windows Vista-based and Windows Vista Service Pack 1-based systems. It was one of eight security bulletins and updates the company made available on April 8.

Users who installed the update, however, soon found their USB devices unresponsive, particularly mice and flash drives. Removing and re-installing the programs reportedly did not immediately solve the problem.

Microsoft confirmed the bug, but declined to provide further details.

"We are aware of concerns that a recent Microsoft update may be causing problems with USB devices," according to a Microsoft spokeswoman. "We are investigating the matter and at this time do not have any additional information to share."

"I have a new system that has been working flawlessly til this patch," a user known as SkyKnites wrote on a Google forum last week. His mouse was later restored, but now "I just get this annoying new hardware found and driver install has failed [notice] every time I reboot," he wrote.

A user known as JB also encountered problems. "I have exactly the same problem as described here, i.e. no cordless mouse and keyboard (via USB)," he wrote. "I run Vista x64 Ultimate which is in a dual boot with XP x64, this means (discovered it today) that my restore points gets whipped. Basically, I don't know how to uninstall the update causing the problem."

Microsoft shipped its first Vista security patch in January 2006 for beta testers running the Windows Vista December CTP (Community Technology Preview) and Windows Vista Beta 1, and warned that the operating system was vulnerable to a remote code execution flaw in the Graphics Rendering Engine.