A. The process for installing an OS on a PC running Virtual PC 2004 (or VMware Workstation, for that matter) is the same as installing an OS on any PC. You simply create a new virtual machine (VM) using the wizards supplied in Virtual PC and VMware Workstation. After you create the VM, you must configure its virtual CD-ROM drive to either connect to a physical CD-ROM drive that contains the installation CD-ROM for the OS you want to install or, if you have an International Organization for Standardization (ISO) file (i.e., an image of the CD-ROM), select that file as the CD-ROM to install. You might have to open the VM's BIOS when the VM starts and configure the CD-ROM as the first boot device. After the VM starts, it detects the CD-ROM and begins the installation. Before you install the OS, you can optionally create a disk of a set size and allocate its space to the OS, which could improve the OS's performance after it's installed and running. Look for a review of Virtual PC 2004 and VMware Workstation 4 in an upcoming issue of Windows & .NET Magazine.