I have 4 XP computers in use now. The oldest is a desktop I built. For that, I bought an XP Pro OEM disk, and had my friendly computer guy install it for me because I wasn't familiar with XP. I still have the installation disk which is labeled as follows:
"Windows XP Professional 1-2 CPU
 OEM Product"
The last 3 XP computers I bought are reconditioned IBM units. They all have a Windows license sticker but no Windows CD. The OS is on a small partition on the C: drive. I assume this is common practice nowadays, but don't know why and it doesn't seem reliable to me.

When the hard drive fails in my newer computers, I will probably lose the "restore" partition, and will lose the use of the computer because I lost the OS which I bought and paid for. Could I install a new hard drive, use the older XP CD to install the OS and use the license number for the appropriate computer? It's the easiest way I can think of. 

1. Will I be able to do that from a practical and legal point of view?
2. Can I use my 1 CD to repair a different computer that has a valid license?
3. Will I have to reactivate the installation(s)? Never done that.
4. The computers are in 2 different locations. Can I copy the CD so as to have a 
   copy with each machine?

I'm not trying to beat the system, just keep what I have paid for. 
Thanks for any info and suggestions. Bob 

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