@Daniel Kendall, Thanks for posting in Q&A. It sounds like you're encountering two distinct issues during your transition from Windows 10 to Windows 11. Let's address each one separately and provide some steps to resolve them.
Issue 1: InstallAccessDenied Error.
The Windows Update services could not access the necessary system locations, Please try the following suggestions to see if it can resolve.
- Disable Antivirus/Antimalware Temporarily:
- Temporarily disable any third-party antivirus or antimalware software during the installation process. Remember to re-enable it after the installation is complete.
- Check for Locked Files:
- Ensure that no other programs (like backup software) are accessing the files that the installer needs to replace. You can use tools like Process Explorer to identify and unlock these files.
- Windows Update Services:
- Restart the Windows Update services.
Issue 2: Compatibility Safeguard
To upgrade to Windows 11 24H2, please configure Feature policy and select Windows 11 24H2 version to upgrade.
https://learn.microsoft.com/en-us/intune/intune-service/protect/windows-10-feature-updates
After checking the update settings in Intune are correctly configured to allow feature updates to Windows 11. For Feature update deferral period (days), it is recommended to be set to 0.
For the compatibility safeguard issue, we can use Windows Update for Business reports to monitor various update health metrics for devices in their organization. The reports provide a list of active Safeguard Holds to provide you with insight into the safeguard holds that are preventing devices from updating or upgrading. Could you confirm if the readiness report you checked without error is this one?
https://learn.microsoft.com/en-us/windows/deployment/update/safeguard-holds
Meanwhile, ensure that all device drivers and firmware are up to date. This can often resolve compatibility issues. Make sure the hardware requirements are met.
Please try the above suggestion and if there's any update, feel free to let us know.
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