G-Tech USB 4 TB & Parallels 12

Trying to use a G-Tech USB 4 tb drive on a Mac Mini running El Capitan and Parallels 12.0.1. The VM in Parallels is also running El Capitan.

When I connect the drive to the Mac Mini, it mounts on the desktop fine. When I try to attach the drive to the virtual machine, it un-mounts from the host machine (as it should) but never appears in the virtual machine. Other drives are fine.

Parallels tech support spent a lot of time with me on this and we were never able to get the drive to show up in the VM. The host machine would require a reboot in order for the drive to show up again.

One Parallels had unmounted the drive from the host Mini, Disk Utility on the VM and the Host machine could not see the drive. Rebooting put it back on the desktop of the Host machine.

Tried two different drives (both G-Technology 4 TB USB) with the same results. Tried updating the firmware of the drive. Nothing.

Is this drive model compatible with Parallels? Assuming it isn’t.

Hello David,

Unfortunately we currently do not have a test system in place for Parallels compatibility. G-Technology 4TB drives are tested for compatibility with El Capitan so both your Host and VM should be able to use the drive. For the immediate future I would contact Parallels for a list of compatible drives. I will pass the information up to our engineers in case they would like to develop a testing procedure for Parallels.

It’s a Parallels issue it seems. Disabling USB 3 support in Parallels clears the issue.

It is an issue in the following setup:
Host: OS X El Capitan
VM: OS X El Capitan

Drives will not be seen in the VM with USB 3.0 support enabled.

In a setup where the Host is OS X and the VM is Windows, with USB 3 support enabled - all is fine.

Hello David,

Thank you for the feedback I will get the information to our support team so that we can create a new knowledge base article.