Version: 17.09.

Command:
docker-machine create -d hyperv --hyperv-virtual-switch "myswitch" name1
Running pre-create checks...
Error with pre-create check: "Hyper-V PowerShell Module is not available"

I found problem in: https://github.com/docker/machine/blob/master/drivers/hyperv/powershell.go
The reason for the problem is the Check is looking for Get-VM. If you have VMware PowerCLI installed it can happen that the test will find the VMware version of the Get-VM command. And this isn't correct and will fail.

The solution is to add the modulename to the Get-VM name.