CompTIA A+® Certification All-In-One For Dummies®, 2nd Edition

3.8. Understanding How to Dual-Boot Windows

Dual-booting — running multiple OSes on the same computer — is different than performing an upgrade. With an upgrade, all applications and their settings carry forward into the new OS. When you dual-boot, you install each OS into a different folder, which means that the applications do not carry forward into your new OS. With a dual-boot scenario, you need to install the applications with each OS installed.

One reason why you might want to dual-boot multiple OSes is to test or support applications in the different OSes. You might also want to dual-boot if your company uses an application that won't function on your primary OS (for example, Windows 2000) but works great in an older OS (for example, Windows 98). You can install both OSes on the computer and then install the application that doesn't work in Windows 2000 on the Windows 98 system; any time you want to use that application, you just boot to Windows 98.

To dual-boot multiple OSes, the following criteria must be met:

• The bootable drive (usually drive C:) must have a file system supported by all OSes on the computer.

• You must install each OS into its own folder.

Here's an example: If you would like to dual-boot Windows 98 and Windows 2000 on the same computer, the first thing you need to do is make sure that your bootable partition (drive C:) is using the file system common to all OSes (in this example, FAT32). After you ensure that you are using a common file system, you may ...