Keep in mind that the IBM OEM copies of XP have their own Product ID...
OEM keys distributed with IBM laptops only work on copies of XP which are designed to be pre-loaded on IBM laptops.
Keep in mind that if you purchase or obtain a copy of XP illegaly, it may work, however won't include any of the drivers, or IBM value added software that the laptop originally shipped with.
Best bet would be to contact IBM (Now Lenovo), and get them to ship out the ThinkPad Recovery disks to reload the OS/Recovery Partition.
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