The "Boot Device Not Found" error indicates that your computer cannot find an operating system on the hard disk. Here are steps to troubleshoot and fix the issue:
1. **Check Hardware Connections**:
- Ensure that the hard drive is properly connected. If you're comfortable, open the case and check the SATA and power cables.
2. **BIOS/UEFI Settings**:
- Restart your computer and enter BIOS/UEFI settings (usually by pressing F2, F10, Del, or Esc).
- Check if the hard drive is recognized. If not, there might be a hardware issue.
- Ensure the boot order is set to prioritize the hard drive.
3. **Run Diagnostics**:
- Many systems have built-in diagnostics tools. Check for a diagnostics option in BIOS or during startup (often F12 or another key).
4. **Repair Boot Configuration**:
- If the hard drive is detected but the OS isn't booting, you may need to repair the boot configuration:
- Create a Windows installation USB/DVD.
- Boot from it and select "Repair your computer."
