Microsoft has launched its widest release yet of the beta version of its troubled next-generation Windows Vista operating system.

The beta can be downloaded now. Released under the heading of the "Windows Vista Beta 2 Customer Preview Program", it will give Microsoft opportunities to receive greater user feedback and make adjustments prior to the product's scheduled debut in January 2007.

Earlier, more limited beta releases have already resulted in changes to security features in the UAC (User Account Control), announced yesterday.

The next full beta version is due in late August, pushed from a scheduled mid-July release.

Windows Vista is the first full revamp of Microsoft's ubiquitous operating system since Windows XP debuted in October 2001.