virtualbox.org

Try add the VirtualBox home directory and programs (all of them in the home directory) to any of the anti-virus/threat detection software (example HP Wolf Security) exclusion list that your host have. Doing this may resolve the GUI issue. However, you may still fail with headless mode.

I have the same problems, reinstalling the operating system does not help. Just did an experiment, installed Windows, chipset and video card drivers and VirtualBox, nothing more. The problem remained, manifested itself 5 minutes after connecting the network.