Hyper-V VM Generation 2

Hello

I'm installing Windows Server R2 foundation in a Vm Generation 2. 

I can create the VM and start de setup. When setup is finished, it has to start de VM, and when it restarts, I get the error "Innaccessible_boot_device". 

I believe it's a problem to write the boot sector, and so the disk can't start, but I don't know why.

If I try to install Windows Server Foundation in a VM Generation 1, and that works fine, but it doesn't recognise the mouse.

Any ideas?

Best regards

Jose Braganca