Hi Randy, I believe you're referring to SCSI UNMAP which was released in the product in 1.4, so should certainly work.
1. Are you mapping the volume directly to the Windows server (ie not through a VMware VMFS layer, for example?)
2. Are you using the Microsoft iSCSI Initiator?
3. Have you tried creating another volume, filling it up with random data, then deleting it again to see if it works on that volume?
I'm just wondering if you got your questions answered. If you did, it would be helpful to the community if you could let us know what worked. That way if others had the same question, we could point them here to your solution.
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