It is the first thing you need to fix the issue as stated above. For that, you need to run the virtual machine showing the error and go to the Devices > Install Guest ...
If your external drive is not detected or recognized in Hyper-V virtual machine, you can follow the solutions and workarounds ...
Make USB devices accessible to a Windows XP virtual machine Your email has been sent Over the past several weeks I have written a series of articles on working with Windows 8’s Client Hyper-V with the ...