Windows won’t start

Windows Update stuck at a percentage and won't finish

During a normal restart, a Windows Update progress screen freezes at a specific percentage (like 30% or 67%) and doesn't move for an extended time, distinct from the general 'Getting Windows ready' message.

Difficulty
Easy
Time
30–90 minutes
DIY cost
$0
Pro cost
$0–$100

Symptoms

  • Percentage number stops changing for over an hour
  • No disk activity light or sound after initial period
  • Happens on a specific, sometimes recurring, update
  • PC won't respond to keyboard or mouse input

Likely causes

  • CommonUpdate download or files corruptedA partially downloaded or damaged update package can hang mid-install.
  • CommonConflicting driver or software blocking the installCertain drivers or security tools can lock resources the updater needs.
  • PossibleLow disk space preventing the update from completingUpdates need free space to stage and swap files during installation.
  • PossibleFailing drive slowing installation to a crawlA struggling drive can make progress appear stalled when it's just very slow.
  • PossibleKnown issue with that specific updateMicrosoft has occasionally shipped updates with bugs affecting certain configurations.

What to do

  1. Confirm there's truly no disk activity (light or sound) for at least 60–90 minutes before concluding it's stuck.
  2. Force a shutdown with a long press of the power button, then power back on; Windows usually attempts to roll back the failed update automatically.
  3. Once back at the desktop, open Settings > System > Storage and free up space if it's low.
  4. Go to Settings > Windows Update > Update history > Uninstall updates and remove the specific update that failed, if it's listed.
  5. Run the Windows Update Troubleshooter from Settings > System > Troubleshoot > Other troubleshooters.
  6. Manually check for updates again; sometimes a newer cumulative update supersedes the broken one.
  7. If the same update fails repeatedly, search Microsoft's release health dashboard or support site for the specific update's known issues before retrying.

When to call a pro

If updates fail repeatedly with the same result even after freeing space and running the troubleshooter, a technician can perform a deeper repair or clean install.

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.