A Microsoft file hosting and synchronization service.
Hi Firouzeh,
For your situation, I truly understand your concern as logically, if the CLIENT folder moved once, it should move back the same way. However, in OneDrive for Business, though, large folder moves can hit per-operation limits, sync performance limits, permissions, locks, or retention rules, so the earlier successful move does not guarantee the reverse move will also be accepted. Based on your sharing, the most likely cause is that the move operation is counting everything inside CLIENT, including all sub-folders, not only the folder itself, which may exceed Microsoft's documented limits (no more than 30,000 files/no more than 100 GB total file size in a single operation).
That said, for the fastest fix in this situation, I would recommend reaching out to your Microsoft 365 administrator and asking for their help. Your administrator can help check whether the folder exceeds SharePoint move/copy limits, whether any items are locked/checked out, or whether retention policies are preventing move/delete operations, and then they can help you move the folder using admin tools.
In case you do not know who your IT admin is, kindly refer to this article: How do I find my Microsoft 365 admin? - Microsoft Support
Hope this information helps you move forward smoothly. If you have any questions, please don’t hesitate to reach out in the comments of this post. I'm happy to assist you further with your concern.
Thank you for your patience and understanding. Hope to hear from you soon.
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