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According to the error message in WUAHandler.log, this could be due to the corrupt local group policies on the client machine.
We may try to regenerate the Registry.pol file follow this article to see if it helps:
- On the client computer, go to C:\Windows\System32\GroupPolicy\Machine.
- Backup the Registry.pol file to a different folder or simply rename it, something like Registry.old.pol.
- Restart the SMS agent host service (SCCM client agent service-CCMEXEC).
- Finally re-run the Software Updates Scan Cycle in the Configuration Manager Actions tab.
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