Is it possible to install Windows XP on a USB drive?

Solution 1:

For what you need, take a look at Bart's PE Environment.

I don't recommend that you actually install a complete version of XP on a flash drive because of driver problems when you use it on multiple computers; it seems like a PE version would be best for your needs.

Solution 2:

Yes it is. Sort of at least: http://en.wikipedia.org/wiki/Windows_Preinstallation_Environment

Solution 3:

Lambert and Villintehaspam are absolutely correct - it is possible and Lambert points out the way I would do it, with BartPE. However! Your computer must support booting from USB mass storage devices (most computers that are fairly recent should do it, but it varies by BIOS). To check, go into your computers BIOS and in the boot options, see if there's an option to boot from USB (same place you would go to set "boot from CD" or "Boot from Floppy".

Solution 4:

If you want to install a fully* functioning version of XP onto a USB hard drive it can be done this way.

(note I haven't verified this myself but it seems to have been posted around the place quite a bit)

http://www.scribd.com/doc/57797562/Install-and-Run-Windwos-XP-From-USB

**Given that this is a hack it is not necessarily going to function 100%*

(Also transferring from one machine to another would require the use of hardware profiles to avoid issues with different machines and should be setup before booting on a different machine: MS KnowlageBase)