Windows won’t start

Hard drive or SSD not detected during startup

Windows either won't boot at all, or the BIOS/UEFI setup screen shows the storage drive is simply missing from the list of detected devices, even though it was working previously.

Difficulty
Moderate
Time
20–60 minutes
DIY cost
$0–$70
Pro cost
$100–$300

Symptoms

  • BIOS storage/SATA info page shows no drive listed
  • PC may show 'no bootable device' or similar because of this
  • Drive doesn't spin up or make any sound on desktops with a mechanical drive
  • May follow moving the PC, a power surge, or opening the case

Likely causes

  • CommonLoose or disconnected data or power cableThis is the most common and easiest to fix cause on desktops.
  • CommonDrive controller mode changed in BIOS (AHCI/RAID/IDE)Windows and BIOS need to agree on this setting or the drive can appear invisible.
  • PossibleDrive electronics or connector failurePhysical damage to the drive's circuit board or connector prevents detection.
  • PossibleDrive mechanical failure (clicking, not spinning)Internal mechanical failure in traditional hard drives stops them from being seen at all.
  • Less commonFailing SATA/NVMe port on the motherboardA damaged port can make an otherwise healthy drive undetectable.

What to do

  1. For desktops, power off, unplug, open the case, and reseat both the power and data cables on the drive firmly at both ends.
  2. Try a different SATA data cable and a different port on the motherboard if available, since cables and ports do fail.
  3. Check the BIOS storage controller mode setting; if it was recently changed, try switching it back to what it was before.
  4. Listen closely to a mechanical hard drive during power-on; repeated clicking or no spin-up sound points to internal drive failure.
  5. If you have another computer, try connecting the drive via a USB-to-SATA adapter to see if it's detected there at all.
  6. For laptops, this typically requires opening the case to access the drive, which may be best left to a professional depending on your comfort level.
  7. If the drive isn't detected on any cable, port, or another computer, treat it as failed and prioritize data recovery before replacement.

Tools and parts

  • SATA-to-USB adapter or enclosure, to test the drive externally
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When to call a pro

If the drive isn't detected after trying different cables, ports, and another computer, it has very likely failed; a data recovery specialist can attempt to retrieve files from a failed drive when DIY methods can't.

Safety

Generally low risk

Generally low risk for a careful person. Stop if anything looks different from what this guide describes.

Related guides

Operator provides AI-generated troubleshooting information. It can be wrong. For safety-critical, electrical, gas, structural, medical, automotive safety, or other high-risk problems, consult a qualified professional.