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I was installing updates one at a time after upgrading to Windows 8 Pro from Windows 7 Home Premium Edition. I got down to two updates left, KB2769165 and KB2770917. Windows update failed with '80071A90'. I ran Window Update Troubleshooter to repair.
The troubleshooter reported 'Potential Windows Update Database error detected 0x80070002' - fixed and 'Windows Update components must be repaired' - fixed. I ran Windows Update and failed again with '80071A90'. I booted into safe mode but Windows Update
service cannot be started in safe mode. I ran 'DISM.exe /Online /Cleanup-image /Scanhealth' and 'DISM.exe /Online /Cleanup-image /Restorehealth'. The restore said 'The component store corruption was repaired'. I rebooted and ran Windows Update on KB2769165.
Now I get update error '800F0923'. What to try next? HELP!!