Hello
Thank you for your question and reaching out. I can understand you are having query\issues related to ReFS not forming with iSCSI.
- Please try to Delete iSCSI Lun from QNAP storage and create a new Lun.
- Please update your Windows ( https://support.microsoft.com/en-gb/topic/kb5010691-refs-formatted-removable-media-may-fail-to-mount-or-mounts-as-raw-after-installing-the-january-11-2022-windows-updates-7a959f37-91b6-4baf-a797-829b0ee86c65) to Latest version then try to Boot Windows in Safe with Networking then try to Re-Format using ReFS.
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