Set up and troubleshoot a dual-boot system

Adding Windows 7
Another great reason to try dual booting your computer is to install the Windows 7 beta. Although Microsoft has now ended widespread access, the OS is still available to members of the Microsoft Developer Network or you may have already downloaded a copy.

This process is relatively simple as, unlike Windows XP, its boot management system is virtually identical to that of Windows Vista. This means the two can be easily installed alongside one another.

If you install Windows 7 on a new primary partition alongside Vista it will detect the old operating system and set up a suitable menu. As with dual booting Vista and XP, the setup of this menu can be adjusted using the bcdedit command from an administrator command prompt in Vista.

If you use the bcdedit /enum command you’ll see that Windows 7 uses an identical bootloader path (\windows\system32\winload.exe) and windows directory (\windows) to Vista, just in a different partition.

Problems with the Windows 7 bootloader can be fixed in a manner almost identical to Windows Vista. If Windows 7 disappears from the boot menu after another operating system is installed, boot from its DVD, choose English UK and the Repair option and follow the instructions given for Vista above.

Removing systems
Windows 7 is currently only available as a beta, so the chances are you will want to remove it once a new version appears.

To do this, boot into Vista and start the EasyBCD tool. Choose the Add/Remove option from the left menu, then select the Windows 7 entry in the list to the top right and click Delete. The operating system will vanish from the boot menu, allowing you to safely delete or reformat and re-use its partition. Windows XP can be removed using the same method.

Linux and Grub
Installing various versions of Windows together can be handy, but using Windows and Linux on the same PC is also a popular choice. The process is a little different, though, as Linux includes its own boot management system. A few are available, but the most common is the Grand Unified Bootloader, or Grub for short.

As with anything Linux-related the exact methods involved in dual booting depend on which distribution you are using, but for this article we’ll use one of the most common: Ubuntu 8.10.

Fortunately, modern Linux distributions are good at spotting other operating systems on the same disk. Install Ubuntu 8.10 in a partition next to Vista, for example, and it will create a boot menu with four options: one for Linux, two for troubleshooting and then a fourth option that starts Windows.

Install Ubuntu alongside both Windows Vista and Windows 7 and this Windows option will open a new menu allowing you to choose between them.

Changing the way that Grub works is as easy as editing a text file, although you do need administrative privileges. Start Linux, open a terminal window and type: sudo gedit /boot/grub/menu.lst

You’ll be prompted for your password, then the file will open. If you’re using a version of Linux that doesn’t use Gnome, such as Xubuntu, you’ll need to use a different text editor such as vi instead of gedit.

The menu.lst file is quite long, but it’s also simple to understand. First look for the line that begins with ‘timeout’ then a number; change the number to alter the time that the menu will appear for before the default operating system is started.

Changing the default operating system is slightly more involved. Look down near the end of the file and you’ll see entries for each of the start-up options: normally three for Linux followed by one for Windows. There is sometimes a ‘spacer’ entry between the Linux and Windows entries, too.

Count from the first entry, which Linux considers to be zero, to the one you want to start by default ­ if you want Windows this will normally be three or four. Enter this number in the ‘default’ row further up, which will normally say ‘default 0’.