Depends on the processor also. Here's a list showing CPU compatibility:
http://www.slashgear.com/intel-cpu-virtualization-confusion-undermining-windows-7-xp-mode-0642923/
Is yours marked Yes or No?
If Yes, it's time to contact HP and ask about the BIOS. They just might have done the same as Sony did, according to the link above.
If No, it might be time for another CPU.
Kees
I have a hp hdx16-1370us laptop running windows seven ultimate. I was able to install the xp mode, but it won't let me run it. I looked up the error message and it said I had to enable virtualizataion in my bios, but there is no setting for it. What can I do?

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