Warning: DFSR is not stable
U-Move cannot back up or restore Active Directory because the Distributed File System Replication (DFSR) service is not stable.
The warning message occurs when the computer is half-way through migrating the System Volume (SYSVOL) from the NT File Replication Service (FRS) to DFSR. You need to wait until the migration from FRS to DFSR has finished before attempting to load AD.
To get the current state of DFSR, open an administrative console and type dfsrmig /getGlobalState. It will report a value between 0 and 9. States 0 to 3 are stable. States 4 to 9 are not stable.
How to Fix This Error
You need to wait until DFSR has finished migration from FRS and is in a stable state (0-3). For instructions on how to migrate SYSVOL from FRS to DFSR (including troubleshooting) see SYSVOL Replication Migration Guide: FRS to DFS Replication (Microsoft Docs).
Overriding the Warning Message
If you override this warning message you might encounter problems with files missing in SYSVOL. This is because SYSVOL is in the middle of being migrated from FRS to DFSR, which could alter the contents of SYSVOL while U-Move is running.
The warning message is typically due to other domain controllers being offline, causing the migration to stall. If the DFSR state value (4-9) has not changed for several hours, and you know that other DCs are offline (and will remain offline while U-Move is running), then it is generally safe to override the warning message.
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