500gb HDD SeaGate not appearing on laptop

I was playing Mass Effect earlier. Got off because of school, so i put it to sleep. When i returned home, I tried getting on steam. The path wasn't found, so I didn't think anything of it. Rebooted. Still no path, so i go to my slave HDD, and surprise! It wasn't there for some reason. I've looked for it in disk management; no where to be found. Ran seatools, no luck. I had around 300 GiGs on there.. please, someone tell me my HDD is just being a lazy ****.

I also turned off the laptop, took out the battery, and both master and slave drives for an hour. NOTHING.



EDIT: when i check disk management, it seems there is a drive of some sort on there, but it has no name.. It's blank. Nothing but *Status* has any information: "Healthy (OEM partition)." When i try to right click, the menu only has a "Help" tab.

Have you tried plugging the Seagate in to a different USB port? Used a different USB cable?

There might be damaged or corrupt system files preventing the Seagate from being recognized. Try running a system file checker scan from an elevated command prompt (option two.) If problems are found, run the scan 3 times and reboot the computer after each scan.

SFC /SCANNOW Command - System File Checker

Please post a maximized screenshot of your Disk Managment window.

Disk Management - Post a Screen Capture Image

Actually, it's an internal drive, secondary. my primary which holds my OS is still intact, which is why i can talk to you still. Seatools didn't read it, but when i checked my BIOS/CMOS, it reads it.

Let me see if i can figure out how to post screenshots.

So, I just found out my HDD is dead. I bought a HDD reader; black X. When trying to read it, it was showing up with messages and saying that i would need to format the drive to use it. going to try to salvage data... wish me luck :[

Edit: thank you for your help

It doesn't show up on disk management screen. Already stated that. So I went to buy a HDD enclosure; The computer read it when i put it in there. So i ran testdisk to see if it could figure out what went wrong. Ran analyse and "deeper scan". The process got to 74% and got stuck, now it's making a very high pitched and annoying whiny sound. It's over. Thank you for your help. I'm now going to proceed to run over babies and puppies.