Trying to connect laptop hard drive to desktop

[SilverNim]

Apologies if this thread is misplaced, I thought it would belong better in a desktop or hardware forum but do not see those options.

My laptop died suddenly and for no discernible reason, so I need to backup my data on my external hd before sending it off to stupid Lenovo. Money is tight and I really want to try doing it myself rather than paying a tech business in town (last experience was very bad...)

I opened up my laptop and got the hard drive out. It uses a combo SATA/power connection. Then I took apart the desktop and stuck the hd in; desktop has the regular one SATA connection and one power cable. They fit onto my hd just fine, but when I turn on the computer it says there's nothing to boot from.

I've Googled a solution for this and searched on these forums, but nothing has been helpful. Is there a way to make this work, or is it just impossible? Any help is very much appreciated.

Laptop is a Win8, desktop is an old-ish Vista.

 

[Paperdoc]

If you computer says it has nothing to boot from, it appears to have become confused about which storage device to use for booting up. It is possible that the mobo itself changed the designated boot device after it found the new HDD attached. You can fix this in BIOS Setup.

If you have not yet used BIOS Setup, it is a set of screens provided by your mobo's BIOS to allow you to make adjustments to what the BIOS does. To enter it, usually you should hold down the "Del" key after you push the front power button, until it completes most of the POST process and stops on the BIOS Setup opening screen. NOTE that, on a few systems, the key to use is not "Del". So watch your screen, especially the lines at the bottom, for a message about which key to push to Enter Setup. If it is not "Del", try again using the right key.

The opening screen of Setup probably shows you the main storage devices present. Check that they look right - their names, maker's names, and sizes. If these are all OK, look for a tab about Advances Setup or Boot Device. (Usually on the right or on the bottom of the screen will be some guides for which keys to use to navigate around the menus.) You are looking for the place where you specify the sequence of devices to try to boot from, often called the Boot Priority Sequence. Some allow you to specify a sequence, one device at a time. Others group them as Optical Drives, Hard Disks, USB Flash Memory, etc, and then give you sub-menus for each group to specify the particular device of that type. The aim here is to tell it to use the devices you want in the right order, and NOT use any other devices. Many people would set this to try the optical drive first, then the particular HDD that you know has your OS on it - the one you always booted from. You do NOT want it to include the transplanted laptop HDD in the list.

When you have that list set your way, back out and remember to SAVE and EXIT so it will remember your changes. The machine should boot properly now.