Storage in a Hyper-V Guest can be referenced by way of a Volume Globally Unique Identified (GUID). This is very useful in scenarios where there are a large number of storage volumes and there are not enough drive letters available to uniquely identify each of them.

After preparing the storage for use by a Guest in either Disk Manager or by using a command line utility such as diskpart.exe, the Volume GUID can be obtained by using another command line utility- mountvol.exe.

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