0x80070643 | Installation failed

What This Code Means

Where Users Usually See This Code

• Windows Update history entries
• Installer dialogs for MSI/MSP packages
• Microsoft Store or app install/repair flows
• Setup logs (CBS, WindowsUpdate, MSI logs)

Why This Code Appears

• A prerequisite component is missing or inconsistent
• A servicing stack/component store issue blocks the update
• Files are locked by a running process or security software
• Permissions or policy restrictions prevent install steps

What Typically Happens Next

• The update/app install is rolled back
• Windows records a failure in update/install logs
• Retrying may succeed after prerequisite repair

What This Code Is Not

• It is not a specific diagnosis by itself
• It is not proof of hardware failure

Troubleshooting Checklist

• □ Restart and retry to clear temporary file locks
• □ Check for pending reboot state and complete it
• □ Run built-in update troubleshooter or repair tools appropriate to the context
• □ Review the closest log (WindowsUpdate.log/CBS.log/MSI log) for the first underlying error
• □ If the failure is tied to a specific KB/app, use the vendor’s official install/repair guidance

Notes And Edge Cases