If so, then was XP fully installed to a partition on the drive, or was it installed as a virtual system?
If the former, Windows 10 should have added the XP to it's bootloader when installing. If the latter, then you need to find the virtual drive it was on and set it up again in Windows 10 as virtual system.
Bought a dell desk top computer with win 7 OS
I had someone install win XP so I could run older software
When available upgraded to win 10]
After installing win 10 my XP will not boot up
What can I do next?

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