Hi, @Chong
Thank you for posting in Microsoft Q&A forum.
After I run the SUP synchronization, it just downloads the software list from upstream server.
The step is just download the metadata of the updates.
When we run the download software update wizard to download the source file and choose "Download software updates from a location on my network", select this setting to download the software updates from a local directory or shared folder. This setting is useful when the computer that runs the wizard doesn't have internet access. Any computer with internet access can preliminarily download the software updates. Then store them in a location on the local network that's accessible from the computer that runs the wizard.
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