News

Microsoft Explains Windows 8 Boot Options

• By Kurt Mackie
• 05/23/2012

Users of Windows 8 will experience a different way of accessing their PC's boot options, which Microsoft described on Tuesday.

Windows 8, which is currently available at the beta stage, boots so fast that there's too little time to access alternative boot options, which are traditionally accessed via the "F" function keys when a system powers up. It's a good problem to have because Windows 8 becomes available quickly to users. The downside is that traditional F2, F8 and F12 key presses to access the BIOS are too slow to interrupt the system boot.

The Windows 8 team took a second look at how to enable those options in the new and faster OS. Chris Clark, a program manager on Microsoft's user experience group, explained in a blog post how users can quickly boot and still have access to traditional BIOS and new Unified Extensible Firmware Interface (UEFI) boot options.

Windows 8 boots in less than seven seconds on a solid-state drive (SSD). Clark said that an SSD actually facilitates the boot speed. The POST period during the startup process now takes less than two seconds and the time allowed to switch to a different boot path can be less than 200 milliseconds, he wrote. That's too fast for a key press, yet PC users may have lots of reasons to enter the firmware. They may want to boot to another Windows OS, boot to another device such as a USB drive, enter Safe Mode (which still exists in Windows 8) or initiate a repair or change prior to a Windows 8 startup.

Boot Options Menu and 'WinRE'
Microsoft added a boot options menu in Windows 8, which lives inside of a "Windows recovery environment" (WinRE). This WinRE design serves as a reference base against any unwanted changes that might be made by software.

"Since the source image for WinRE contains drivers and files that are kept separate from the main Windows installation, it's not affected by any software changes and is a reliable environment to begin troubleshooting from the boot options menu," Clark explained in the blog post.

The Windows 8 boot options menu is easily accessible throughout the operating system, even after the system has booted. It also can be accessed during a system restart by holding down the SHIFT key. Microsoft additionally added a new tag for command-line users to access the boot options menu. They can type "shutdown.exe /r /o" to get to that menu.

Most of the traditional BIOS preboot options can be accessed through the boot options menu. Users can boot to USB drive or DVD recovery disk. They can boot to "another installed version of Windows." They can refresh, reset or troubleshoot the PC. The boot options menu is also the place for developers to disable drivers signing and to enter the debugging mode, Clark explained.

System Failure
If a boot fails on a first try, Windows 8 will try again. However, if that second attempt also fails to start the machine, "Windows RE is automatically loaded and launches the specialized Startup Repair Tool," Clark stated. He didn't provide much detail about this tool, although he said that it specifically fixes errors in the boot process.

Those users of Windows 8 who fail to boot on the second try also get taken automatically to the boot options menu screen.

The kind of hardware that's used with Windows 8 will make a difference for users in terms of what boot options they'll have. For Windows 8 running on older "legacy" hardware, the features of "booting to firmware settings and booting directly to a device" won't be accessible through the boot options menu, Clark explained. Instead, those features can be accessed by the older method of pressing F2 to enter the BIOS settings. Microsoft officials have claimed that Windows 8 will run on hardware that was capable of running Windows 7.

While Clark didn't mention it, booting to a Linux operating system on a Windows 8 machine appears to be a whole different kettle of fish that's associated with a UEFI "secure boot" controversy. Users who want to do that probably won't be able to do so on a Windows RT device (also known as "Windows on ARM"). This potential limitation has raised the ire of many people in the Linux community.

The new ARM-based Windows 8 devices will use the newer UEFI-based firmware, rather than BIOS, to boot the system. UEFI features a secure boot certification process that reduces the risks of booting into malware, but that feature doesn't play well with Linux OS variants. Microsoft will require hardware manufacturers to have the secure boot feature turned on by default in new Windows RT devices, but users of x86/x64 Windows 8 machines apparently will be able to turn that feature off.  

Microsoft has said that it expects to deliver a "release preview" of Windows 8 in the first week of June. The OS may be rolled out as a final product sometime in the fall of this year.