If you launch the virtual machine console in Oracle VM Manager and an error is displayed, you may not have installed the VNC viewer on the Oracle VM Manager host computer. To resolve this problem, install a VNC viewer on the Oracle VM Manager host. You can also install a VNC viewer on the client accessing the Oracle VM Manager Web Interface. Oracle recommends you also install a VNC viewer on the Oracle VM Manager host computer so that if a client does not have a VNC viewer, this problem does not occur. See Installing and Upgrading Packages Required For The VNC and Serial Console in the Oracle VM Installation and Upgrade Guide for more information on installing the VNC viewer.