I had the same problem. I am running the sandbox 2.1 on VMware Player / Windows 7. Tried Everything mentioned above. Setting a host only connexion wasn’t enough to rid me of the connexion error because the VM couldn’t start the new network adapter. It turned out that I had disabled the VMware network adapters on the host machine. Once I enabled them, I got the HDP splash screen immediately. I hope this will help the rest of you.