What do you need? A 4GB or larger USB flash drive or hard-drive and a computer with a BIOS that supports booting from a USB device. Almost every computer made in the past three years or so supports this feature. Also, you’ll need your Windows Vista or Windows Server 2008 install disc or ISO (for this, I used a licensed copy from my MSDN subscription).

• Open the Disk Management console (run “diskmgmt.msc”)
• Format your flash drive as FAT32 and set the partition as active/primary.
• Copy the entire Windows disc to the USB storage device – the easiest way is by running “xcopy D:\*.* /s/e/f E:\” at the command prompt (where D: is your optical drive/mounted ISO and E: is the USB flash drive.).

Note: If you are using a large external hard-drive, you’ll want to create a partition smaller than the drive itself since FAT32 has certain size limitations. In my case, I chose to make a 6GB active partition and left the rest unpartitioned.

Remember, this is not only useful for computers with defunct or non-existant optical drives – you can also use this for installing Windows on multiple machines quickly as you’ll find it significantly quicker than reading off a DVD.

I have not tested this with Windows XP, however I see no reason why it would not work. If you encounter issues where you cannot boot successfully from the USB drive after the copy, you might need to run the “bootsect.exe” from the command line. Check MS Knowledgebase for more detailed information on this.