HDD I/O device error
I recently built my own rig. For an ssd I used a sandisk ready cashe and for HDD Seagate 3tb. But the HDD never shows up on this PC (I am using windows 8.1 pro) and It says it only has 3.9 GB when it is supposed to have 3000. When I go to disk management and try to format it and make it online it says "The request cannot be performed because of an I/O device error" please help me to where I can use my HDD...
I've struggled with a similar problem before:
1/ Try to 'Safely Remove' the external drive and then reconnect it again, sometimes a simple reset can be the solution.
2/ The error might be because of the drivers on your computer. So I'd advice to try the HDD on another PC/laptop.
2/ Another thing I'd do is check if you have the latest firmware update of your external drive. If it is outdated, it can reflect the performance of your drive.
3/ Can you access the drive through Device and/or Disk Management? If yes, what is the information the tools show about the drive?
4/ Another thing you can try is to check the HDD through Windows' Command Prompt (run it as administrator), type chkdsk x: /r (where x: is the drive letter of your external drive), this will locate bad sectors and recover readable information.
Keep me posted if any of the suggestions worked with you!