Swapping hard drives

[jonnyboy23]

I recently bought a windows 8 laptop from a pawn shop and I was trying to downgrade to windows 7 pro. After the purchase I noticed that it did'nt have a disk drive and that's where i messed up. Im fixing my co-workers laptop at the moment and its an hp (mine is a Dell) so i decided to switch the hard drives and install windows 7 on it since it has a disk drive on it. when I switched the hard drives the laptop was telling me no bootable devices what could be the problem? it worked perfectly fine with the hp and i dont have a disk reader on hand

 

[bumzag]

Most likely the previous owner wiped the HDD clean, possibly deleting Windows as well. That, or the OS is corrupted and the BIOS can't detect Windows whatsoever. Or, finally, the boot sequence is pointing to a device other than the HDD, such as the USB hub or LAN.

 

[Layback Bear]

Swapping hard drives from on branded computer to a different branded computer will not work well if at all.
The information on the different motherboard will not match the information on the drive with the operating system from the other computer.
If it did boot, it would be flagged by Windows 7 as counterfeit.
When a computer manufacture installs Windows 7 on one of their computers it is only designed to be used on that computer and is not transferable to other computers.

Drivers for a HP computer are most likely not the same drivers that will work on a Dell computer.

 

[Ztruker]

If the laptop doesn't have a optical drive, put the Windows 7 install on a flash drive, then boot the flash drive to install.

Use Imgburn to create an ISO file from the DVD on any computer that has a DVD drive.
Use Rufus to take the ISO and create a bootable flash drive to install from. Can also be done on any computer.