Hi sivi1 nesivi1,
Hope you're doing well.
Please open PowerShell as an administrator and input the following command to check NumberOfColumns:
**get-virtualdisk -friendlyname diskname | fl ***
If we use two physical disks to create the "StoragePool", the "NumberOfColumns" of the "StoragePool" will be 2. If we want to extend the "Storage Pool" or "Virtual Disk", we must add 2 or a multiple of 2 the same size disks.
Please note that we must ensure there is data backup in place.
Best Regards,
Ian Xue
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