Can you shar the screenshot of error message?
Also is the Storage device working now?
You can kill the running process for VM and then try to register it.
VMware KB: Powering off a virtual machine on an ESXi host
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T. Sateesh
VCIX-NV, VCAP 5-DCA/DCD,VCP 6-NV,VCP 5 DCV/Cloud/DT, ZCP
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