Guest is not on the full screen

[CorinneS]

I have virtualbox on Ubuntu 18.04
Virtualbox 5.2.18
I don't know how to gat the guest VM windows 10 on full screen.

[socratis]

First of all, don't even bother doing the following, unless you've resolved the installation of the official VirtualBox, and not the Ubuntu fork.

When you install the official VirtualBox, we need to see a complete VBox.log, from a complete VM run:

• Start the VM from cold-boot (not from a paused or saved state) / Observe problem / Shutdown the VM (force close it if you have to).
• With the VM completely shut down (not paused or saved), right-click on the VM in the VirtualBox Manager and select "Show Log".
• Save only the first "VBox.log", ZIP it and attach it to your response. See the "Upload attachment" tab below the reply form.