Hi Ahmed.M,
Thank you for your question. As per my understanding, you have a VM running on a cluster and you need to remove a VHD attached to it. The VHD is stored on a CSV and you want to know if you could just delete it. Please correct me if there’s any misunderstanding.
To delete the VHD file, you should stop your VM and disconnect the VHD in the settings page of the VM role in Failover Cluster Manager. Then you could delete the VHD file and the space it occupied will be returned to CSV automatically.
Please make sure you have backed up the all data you stored on the VHD.

Best Regards,
Ian Xue
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