If in addition to Parallels Workstation you have installed on your computer virtual machine software developed by vendors other than Parallels Software International Inc., a problem with a network adapter for an external virtual machine is possible. Alternative virtual software may assume Parallels virtual network adapter, Parallels Host-Guest Virtual NIC, to be a real network interface and connect an external virtual machine network adapter to it. This problem is especially probable if the external virtual machine chooses network adapter automatically.
If the problem described above occurs, you will receive an error when trying to access Internet in an external virtual machine. To solve the problem:
The Parallels Workstation adds Parallels Host-Guest Virtual NIC network adapter to the list of network adapters in primary operating system during the installation process. This adapter is required for host-only network.