HDD from a different computer

[ggarso]

One of the computers at work today died (motherboard) My boss went and bought a new Compaq. Old computer was an Emachines. All the programs for our equipment work on XP new computer is Vista. My question is he tried to take the XP Emachines HD and boot it in the new Compaq with its HD disconnected. It would not boot, is this because it came from a Emachines or is something wrong?
Thanks for the help!!

[BillLeeLee]

The drive from the emachines won't boot probably because its HAL, drivers, and windows registry were for the old machine, not for the new machine (so, for example, the mass storage controller in the new Compaq is not supported by any drivers in the existing drive).

Back up the data on the drive and repair Windows XP. You might have to do a full reinstall.

[ggarso]

Thanks for the help. Kinda what I thought but wanted a better opinion than mine.