Old harddrive, new system

[PlatinumDragoon]

I took the harddrive from my dad's computer and put it into my old box. My old system is a Intel P4 on an Intel board. It has 1 gig of ram and a new power supply. In the bios, the board sees the harddrive and everything else.
However, windows Xp will not load in any mode. A window comes up says that a hardware change is resposible.
Without reformatting, how do I bring Windows XP back online?
Thank you for any help.

Platinum Dragoon.

 

[Mr_Threepwood]

Does the old disc that you put in have windows on it(I mean was it as the Operating system disc on your dads computer)?

 

[PlatinumDragoon]

Yes, the old harddrive has windows xp on it. It worked great on his old slow system. I just added an Intel board, 2 ghz P4, and a gig of ram. I don't think its a HCL issue.

 

[Ste]

Boot off of XP disc, goto install windows, when it detects an OS already on disc, select repair.

 

[PlatinumDragoon]

Tried that. Now, it asked me for an administater's password. I have never installed a password on either system and I built both from the ground up.

Is there a default password on XP discs, or is this somehow on the harddrive?

 

[computer_test_2]

There shouldn't be a password.

 

[PlatinumDragoon]

I know