Did you use Windows 8 Consumer Preview(the client version)? If so, I would like to let you know that MPIO is a Windows Server feature. In Windows Server “8” Beta, you can proceed to Server Manager, click Manage on the right top of the windows, select “Add Roles
and Features, then you will be able to find “Multipath I/O” in Features.
You can also use the following command to enable it:
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