Problem with Windows 7 HDD not launching on various machines
Problem with Windows 7 HDD not launching on various machines
You're facing a common issue when mixing hardware from different systems. Since the old HP hard drive is from another machine, it might not be compatible with your Dell setup or Windows 7. Check if the drive supports the same interface (SATA vs. IDE) and consider using a USB adapter or a different drive type. The lack of a hard drive in your Dell setup means you'll need to install the old drive manually, but compatibility could still be a problem.
It might have drivers for the motherboard or other components that don't work well with the system's hardware. This is when you need to reinstall. You can often use a Windows 7 key to unlock Windows 10, and the bootable disc for W10 is usually available for free.