I upgraded my PC, new motherboard, etc.
I want to use my old HD. The BIOS recognizes it, starts booting windows but a message saying it is unable to boot appears.
YES you remove your old data then reformat your HDD
Insert your boot up floppys/or XP CD.
With floppys
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At the A:prompt type fdisk and press return.Then proceed to delete the logical partion,once deleted. Create a new partition.Now leaving your floppy in its drive reboot your system,then at the A:promt type format c: and press return,if asked for character press return.Finally at the last A:prompt insert windows CD and type in setup and press return.Windows will now install.
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With XP CD
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Ensure your BIOS setup BOOT is set to CDROM as 1st option. Then slightly different to above,insert windows XP CD and restart PC.Follow on screen instruction as for new installation.(It may allow you to format here) if not? follow the steps below.
It will give you the option to delete partion so do so,then choose to create a new partition.Once done simply choose format as usual and your works as good as done,simply follow on screen instructions.