Why the hard disk is not detected?
If your new hard disk is not detected by or Disk Manager, it could be because of a driver issue, connection issue, or faulty BIOS settings. These can be fixed. Connection issues can be from a faulty USB port or a damaged cable. Incorrect BIOS settings may cause the new hard drive to be disabled.
How long can a hard drive hold data without power?

Under those ideal conditions, hard drives are predicted to be able to retain their data for 9 to 20 years.
How do I revive a failed hard drive?
How to Fix Hard Drive Failure
- Clean Out the Computer Vents. Over time, dust and debris will visibly clog up the vents on your computer.
- Check the Power and Data Cables. Your hard drive has power and data cables that connect to it from the computer power supply and motherboard.
- Check Your Bios.
- Listen for Sounds.
What happens if hard disk is not working?
If a hard drive stops responding, it could be a corrupt or virus/malware infected file on the hard drive that must be removed to fix the drive error. You can use Windows Defender tool in Windows or leverage a reliable third-party antivirus and anti-malware tool to quarantine the infected file(s).

How long can HDD hold data without power?
Under those ideal conditions, hard drives are predicted to be able to retain their data for 9 to 20 years. The long range is due to the different architectures used in the manufacturing of modern hard drives.
Can HDD failure be fixed?
Only specially-trained expert engineers in a professional data recovery service can repair hard disks safely and effectively. And even then, a repaired hard disk drive will not perform well enough or last long enough for it to be used.
What happens when a hard drive dies?
Symptoms Of A Hard Drive Crash Blue screen on a Windows computer, also called the Blue Screen of Death, or BSOD. Computer will not start. Computer attempts to boot but returns a “file not found” error. Loud scratching or clicking noises coming from drive.