Microsoft has blocked a work-around that let users boot directly to the Windows 8 desktop, the author of an upcoming book on the operating system confirmed today. "Microsoft made some changes to Windows that prevent the .scf hack from working correctly," Rafael Rivera said, as ZDNet reports.

The ".scf hack" Rivera referred allowed users of Windows 8 Consumer Preview to circumvent the tile-based Start screen and automatically shift to the familiar desktop after logging on.

Other hacks, including some that restore the Start button to Windows 8, have also been blocked by Microsoft.

Microsoft announced the Windows 8 RTM, or "release to manufacturing," milestone last week. Final copies of Windows 8 Enterprise leaked to file-sharing websites a day later.

Although previews of Windows 8 could be modified to insert a homemade Start button and with more work, bypass the Start screen at log on, Microsoft has invalidated those work-arounds in the RTM build, said Rivera.

Instead of a Start button, Windows 8 uses a "hot corner" at the lower left. When that hotspot is touched or clicked, the interface switches from the traditional desktop UI to the tile-centric environment, or vice versa.