Hello,
The Activity Monitor in Windows Updates may not accurately reflect the source of updates when a device is set to use WSUS. This is because the Activity Monitor only shows the source of the update package, not the source of the metadata used to determine which updates are needed.
When a device is set to use WSUS, it will still contact Microsoft's servers to download the metadata that is used to determine which updates are needed. However, the actual update packages will be downloaded from the WSUS server.
Therefore, you can ignore the Activity Monitor in this case and confirm that the updates are indeed being downloaded from the WSUS server by checking the WSUS console.
Best Regards,
Hania Lian
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