0x80070BC2
Microsoft Windows Update
Severity: ModerateWhat Does This Error Mean?
Windows Update error 0x80070BC2 means your computer has a pending restart from a previous update. Windows will not install new updates until the pending restart is completed. The fix is usually as simple as restarting your computer.
Affected Models
- Windows 10
- Windows 11
- Windows 8.1
- Windows Server
Common Causes
- A previous Windows Update installed successfully but requires a restart that has not happened yet
- A software installation or uninstallation left a pending file replacement that blocks further updates
- The Windows Update registry keys are stuck in a 'pending reboot' state
- A Group Policy setting is delaying or blocking required restarts
- Windows Component-Based Servicing (CBS) has pending operations waiting for a reboot
How to Fix It
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Restart your computer. Save all open work, then go to Start > Power > Restart. Do not just shut down — make sure to choose Restart.
A full restart (not a shut down and power on) is what Windows needs to process pending update operations.
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After restarting, run Windows Update again. Go to Settings > Windows Update and click 'Check for updates.'
In most cases, the error clears immediately after one restart and updates install normally.
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If the error persists, run the Windows Update Troubleshooter. Go to Settings > System > Troubleshoot > Other troubleshooters > Windows Update > Run.
This tool automatically detects and fixes common Windows Update problems including stuck pending restart states.
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Manually clear the pending restart registry key. Open Registry Editor (regedit), navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate\Auto Update\RebootRequired — and delete any values inside it.
Only do this if the troubleshooter did not help. Always back up your registry before making changes.
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Reset Windows Update components. Open Command Prompt as Administrator and run these commands one by one: net stop wuauserv — net stop bits — ren C:\Windows\SoftwareDistribution SoftwareDistribution.old — net start wuauserv — net start bits
This clears the Windows Update cache and forces a fresh start of the update service.
When to Call a Professional
If restarting multiple times does not clear the error, a technician can use registry tools and the CBS log to diagnose exactly what is blocking the reboot completion. This is rarely needed for home users but can be important on managed business computers.
Frequently Asked Questions
Why won't a regular shut down fix this?
Modern Windows computers with Fast Startup enabled do not fully shut down when you click 'Shut Down.' They save the kernel state to disk instead of fully restarting. Choosing 'Restart' forces a complete reboot that properly processes pending update operations.
How do I know which update is stuck as pending?
Open Event Viewer (search in Start menu), go to Windows Logs > System, and look for entries from 'WindowsUpdateClient.' These entries will show you which update is waiting for a restart to complete.
Is it safe to delete the RebootRequired registry key?
Yes, in most cases it is safe for home users. This key is just a flag that tells Windows a reboot is needed. Deleting it clears the flag. If the underlying update truly needed a reboot to finish, Windows Update will re-queue it.