How to adapt the screen size of the VM

[cm39]

Hi,
I have this configuration:
- windows 10 with VirtualBox 6.0.2
- a Ubuntu VM version 18.04
The problem is about the screen size of the VM. It doesn't fit the VM size when I extend this one.
See the image below :
http://pix.tdct.org/upload/original/1547827679.png
If I extend the size of the VM holding the right down part, it can fit my main screen but the Ubuntu screen keeps always the same size..

So what could be the solution ?
Thanks,

[r_a_ven]

This is the exact same problem I am having. I have always had this issue on Windows host OS. In my case I am running minimal CentOS on windows 10 pro.
I have no GUI server; just the basic console. I thought it would be far easier to configure.

Adding Guest additions does not work.
Vbox oracle extensions do not work.

I am at my twits end.

[socratis]

This is the exact same problem I am having ... I have no GUI server; just the basic console.

I'm going to start with "r_a_ven" because, no, it's not the same problem. Nothing to do with it. You do not have a resolution in a console, it's rather fixed. Unless there are some tricks from within the guest that you can use, something about grub, can't remember exactly...

The problem is about the screen size of the VM. It doesn't fit the VM size when I extend this one.

Have you tried changing the resolution from within the guest? That's how you'd do it in a normal computer, no?

I see the GAs CD there, I don't know if you installed the GAs, try it. If that doesn't work, we need to see a complete VBox.log, from a complete VM run, where the problem occurs:

• 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.