By default, a freshly installed virtual machine runs on emulated hardware that provides only basic functionality. The "CD image" (actually an ISO file named VBoxGuestAdditions.iso ) contains custom drivers that unlock these key capabilities: Guest Additions - Oracle Help Center
The is an ISO file containing device drivers and system applications designed to optimize the performance and usability of a guest operating system running inside a Oracle VM VirtualBox virtual machine. guest additions cd image
| Issue | Workaround | |-------|-------------| | Linux additions fail to compile (kernel headers missing) | Install linux-headers and build-essential | | Secure Boot on Windows/Linux | Sign drivers or disable Secure Boot | | Wayland display issues (Linux) | Switch to Xorg or use basic features only | | macOS guest not supported for full additions | Limited to basic mouse integration | By default, a freshly installed virtual machine runs