In the Properties window, go to the Compatibility tab.Right-click the desktop shortcut of VirtualBox and choose Properties.To fix the error failed to open a session for the virtual machine, you can choose to open the VirtaulBox as administrator. In this section, we will walk you through how to fix the VirtualBox error failed to open a session for the virtual machine. 4 Ways to Fix Failed to Open a Session for the Virtual Machine So, in the following part, we will show you the solutions. If you also has come across this error, here are some suggestions that can help you to fix the error that VirtualBox failed to open a session for the virtual machine. Some users complain that they encounter the error failed to open a session for the virtual machine when trying to start the virtual machine from the VirtualBox on Windows 10.