Ubuntu on VirtualBox with small screen

Question

After installing Ubuntu 18.04 on Virtual Box 6.1 the screen is small and we are unable to install Guest Additions.

If you try to access the mounted guest additions ISO image directly, you get mount errors.

Answer 1

On the internet people are giving different solutions that could end up corrupting the installed guest OS. After trying multiple times to have the screen size resolved with Ubuntu 18.04, Virtual Box 6.1 running on Windows 10, here are exact steps that will help:

Make sure to install VirtualBox Extension pack from - https://www.virtualbox.org/wiki/Downloads

1. Opt to do "normal installation" with following selected - "Download updates while installing Ubuntu" and "Install third-party software for graphics and Wi-fi hardware and additional media formats"
2. After installation, system will restart but the screen will be small
3. IMPORTANT STEP: If you click on 9 dots (Show Applications), you should see icon for "Software Update" (spinning circle with A on it). Click on it and ensure all the pending updates are installed
4. Once all the software updates are completed, open terminal and run following command - sudo apt install gcc make perl
5. Then click on Devices > Insert Guest Additions CD image
6. While guest addition is being installed keep focused eye on the output. If any dependencies is missing, you will see it on the screen. If all dependencies are resolved the auto-run should install the guest additions for you and clearly state that install additions will not activate until restart.
7. Restart the OS and you should see full screen on load.

With latest VirtualBox version 6.1.4, the above did not work as the issue was in Guest Additions 6.1.4. Installing Guest Additions 6.1.5 from https://www.virtualbox.org/wiki/Testbuilds solved the problem. For details refer -https://www.virtualbox.org/ticket/19336

Also I had to assign more display memory. After logging in I have to press Ctrl + F or view > full screen to let the screen scale.

Hope this helps!

Answer 2

Changing the Screen resolution of the Ubuntu worked for me.

Go to Displays Setting and change Resolution.