Does this help
Can I make a second copy of my Windows operating system software for my portable computer?
The End-User License Agreement (EULA) for many Microsoft application software products contains the following sentence: "The primary user of the computer on which the SOFTWARE PRODUCT is installed may make a second copy for his or her exclusive use on a portable computer." If your EULA contains this sentence, then, subject to the conditions mentioned, you may make a second copy of the software. Note that you must be the primary user of the computer on which the software is installed. The primary user is the individual who uses the computer most of the time it is in use. Only that individual is entitled to use the second copy. Furthermore, the software must be installed on the local hard disk of your computer; you are not entitled to make and use a second copy on your portable computer if you run the primary copy of the software from a network server. Finally, only one secondary copy may be made; you may install this copy on more than one portable computer.
Please note that many Microsoft products are copy protected and it will not be technically possible to make a second copy of the disk. If you are a Licensee of software that includes copy protection technology, please call the Product Support Services number provided for that specific product to learn whether or not unencrypted disks can be obtained.
http://www.microsoft...t_eula_say.mspx