@Biswajeet Kumar
If you are using Azure Files, Azure File Sync provides a modern replication and synchronization mechanism that may be used in place of DFS-R if replication is also desired. We recommend checking to see if this fits your use-case, more information can be found on the planning page.
If you are set on using DFS-R with Azure Files please confirm you have setup DFS to properly work with Azure Files. We have guidance on our documentation page here.
Hope this helps! If you are still facing issues please let me know and we will be happy to work with you more closely to resolve your specific error.
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