I hit a problem recently in VMware Workstation (v11) where I couldn’t connect a USB storage device to my VM, as it claimed that “The connection for the USB device x was unsuccessful – The host is currently using the device …”. I knew that there weren’t any application or OS process accessing it, so thought it may be the USB pen drive itself.
Looking within the Windows Explorer window I confirmed that the OS could see the device and that it was accessible (see below).
I had the USB key inserted into one of the two front USB ports of my PC, both USB 3.0 ports.
Moving the drive to one of the USB 2.0 ports on the back of my PC, and then trying to connect the USB pen drive to my VM, it worked successfully without any warnings or errors. I repeated the process to ensure that it wasn’t a fluke, though I could replicate the same warning message again and then have it work in the rear USB 2.0 port, but not a front or rear USB 3.0 port.
Below: After inserting the USB pen drive into a USB 2.0 port, I could then connect it to the VM within Workstation, and have it be presented up to the VMware vSphere install I was performing (for a bootable pen drive copy of vSphere).
Having a quick scour of the internet pulled up a few articles (eg: this VMware KB for an earlier version of Workstation) indicating that there can sometimes be “issues” between VMware Workstation and USB 3.0 ports. There will no doubt be a technical reason for this, but for now I’m happy just using a USB 2.0 port and thought that I’d pass on my experience to others, who may find themselves with the same warning message. I should also point out, that there other known instances where legacy USB 2.0 devices have issues connecting via USB 3.0 ports, so it may be an incompatibility between the chipset/driver used on the devices and the controller used by the USB 3.0 port.