Using Extra USB Ethernet adapter

I want to be able to use my Parallels VMs on a separate interface from the other applications on my iMac. I have a USB Ethernet adapter (the one designed for the MacBook Air) and have used that for other applications in the past (so I know it works). I have configured it to have a fixed ip address in the Mac Network Preferences, and then set it as the adapter to use for bridged ethernet in Parallels (I am using Parallels 3.5636). It seems to configure OK but when I try to run a virtual machine I get a message saying "Problem with network adapter is detected. Please check... "[etc], and I get (unsurprisingly) no network connectivity in my VMs.

I have previously been using my AirPort connection as the bridged ethernet adapter, but I need that now for my Time Capsule. Can anyone advise how to configure the USB Ethernet adapter so that it will be properly recognised by Parallels VMs?

Thanks,


Ian.
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