Hi AmitHaridas-9125,
After you install Azure File Sync in the server you must run the initial server registration. This establishes a trust relationship between Windows Server and Azure, to be used later to create server endpoints on the server representing the folders to be synchronized to Azure. That being said, for this to happen you need to ensure that the server is connected to the internet and that Azure is accessible, along some other requirements listed in Manage registered servers with Azure File Sync.
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