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That fixed my problem. I didn't have USB in the hardware list. I had to shutdown the VM in order to add it (that's why I didn't find it in the...
I did before posting, and it did not help. the device mounts on the mac host, but there is no 'external device' menu, and the VM is not available...
on MacOS 10.11.6 with a windows 10 guest, using Parallels Desktop 12.2.1 : I cant attach a USB thumb drive to the Windows guest. in de VM's...