Hyper V File Transfer From Host To Guest. Mount it in the host it will be a blank new drive so you will have to format it perhaps fat32 for compatibility. After you enable the guest service you can start pushing files into a vm from the hyper v server by using filesource host parameter.
We just setup a new server running server 2012 standard with hyper v running two server 2012 standard guests and saw the exact same thing you are describing. You can do that in disk management. Hyper v guest services 2.
Right click the virtual disk file and select mount.
Just use the vmname parameter with the new pssession cmdlet on the hyper v host to create a new session to the hyper v vm and store it in a variable. Then on the vm please share the files to host. As mentioned remote desktop will do file drag and drop. When i 1st created this guest vm the file transfer worked from the windows host machine running hyper v server 19 to the centos 7 guest vm.