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I just did a conversion from an Acronis echo backup of a windows XP machine, and I am having trouble getting the USB device to pass through (in this case a USB license dongle). I added the USB controller, but the USB devices will not show up in the list.

I can see the dongle from a fresh install of Server 2008, but not this machine.

One note, when opening up the settings I get this error:

"An IDE controller is found but the virtual machine does not support this option."

After clicking the "OK" button, I get this:

"A flat backing option was not found"

Any ideas?

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Not every device works with passthrough, that's why why have a HCL, for instance I have some USB disks that work and others that don't. – Chopper3 May 23 '11 at 12:43

Not a solution but an easy workaround: USB license dongles, especially the ones from Aladin, have been found to work quite well with USB network hubs like this Belkin model. This way, you would not need any virtualization support for the device but could simply access it over a network connection.

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Cool! I didn't realize that would work, unfortionitly we don jave the budget for one. Will keep that in mind for the future though. – SkinnyGeek1010 May 25 '11 at 17:02
up vote 0 down vote accepted

I had to end up reloading my Acronis Echo image. Using the converter messes it up somehow. Using the Acronis boot disk to restore does the job though.

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