I just installed this software off virtual box, i downloaded the ISO off the official ubuntu website, was the lastest LTS.
I attempted to install Guest Additions using the 'Insert Guest Additions CD Image". Result:
Verifying archive integrity... All good. Uncompressing VirtualBox 5.2.0 Guest Additions for Linux........ VirtualBox Guest Additions installer Removing installed version 5.2.0 of VirtualBox Guest Additions... Copying additional installer modules ... Installing additional modules ... VirtualBox Guest Additions: Building the VirtualBox Guest Additions kernel modules. VirtualBox Guest Additions: Look at /var/log/vboxadd-setup.log to find out what went wrong VirtualBox Guest Additions: Running kernel modules will not be replaced until the system is restarted VirtualBox Guest Additions: Starting. VirtualBox Guest Additions: modprobe vboxsf failed Press Return to close this window...
Inside the /var/log/vboxadd-setup.log:
Kernel configuration is invalid. include/generated/autoconf.h or include/config/auto.conf are missing. Run 'make oldconfig && make prepare' on kernel src to fix it.
Full version of log file can be found here [?]