Please help! When I try to boot, I get a message stating no hard drive or operating system was detected. We replaced the hard drive and the cable that connects it to the mother board but, the problem was not corrected. The O.S. is Windows 7.
Windows 7 is probably not installed on the drive. If HP does not provide recovery discs unless you pay an extra 10-20 dollars on the config, or online after it is bought... Recovering requires the original laptop settings, it is probably an OEM License, OEM licenses work this way:
1. An OEM copy is usually BIOS-locked to the motherboard, and will not recognize changed backbone hardware.
2. An OEM license ties it to the first computer it's installed on. A different, non-identical motherboard is treated as a different computer, and even if it weren't BIOS-locked and you could install it, you would not have a valid license and you wouldn't be able to activate it.
Basically, you will need a new license of Windows 7, You can buy one from Microsoft.com for 119 dollars if you get home premium.