@Anon4343 Welcome to Microsoft Q&A Forum, Thank you for posting your query here!
Firstly, apologies for the delay in responding here and any inconvenience this issue may have caused.
As I understand you are not able to Register the server using (PowerShell) the server registration UI as per the below image am I correct?
- If the server registration UI did not start immediately after completing the installation of the Azure File Sync agent, it can be started manually by executing C:\Program Files\Azure\StorageSyncAgent\ServerRegistration.exe.
- If the Azure Sync Service ( Azure File Sync Agent) is already been registered to any VM and Cloud Endpoint point is deleted still you may face this kind of issue-> In the Azure portal, navigate to the Registered servers section of the Storage Sync Service. Right-click on the server you want to unregister and click "Unregister Server".
Note: Unregistering a server will result in cascading deletes of all server endpoints on the server. You should only run this cmdlet when you are certain that no path on the server is to be synced anymore.
This command registers a server to a storage sync service which creates a trust relationship. PowerShell or the Azure portal can then be used to configure sync on this server.
Register-AzStorageSyncServer -ResourceGroupName InfraRG -StorageSyncServiceName ahda1 -Debug
If the issue still persist & it's New VM you can un-install the File Sync agent and re-install the Azure File Sync agent.
If you have any additional questions or need further clarification, please let me know.
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