Resolution doesn't change when resizing Virtualbox window

I've installed Ubuntu 64bit on Virtualbox 4.2.16. Guest Additions were installed in Ubuntu as well.

However the display resolution of Ubuntu does not seem to change as the Virtualbox window is resized or if we were to go into Full Screen mode. Any ideas?

Solution 1:

I had this problem as well running a newly installed version of VirtualBox (VirtualBox 6.0). I tried installing the aforementioned packages but had no luck. My solution was simpler than I had anticipated. While the machine is powered off, go to:

Settings (of the VM) > Display > Graphics Controller > and select "VBoxVGA"

VirtualBox had set this option to "VMSVGA" by default for me. Fortunately, I noticed this subtle difference when comparing the settings between some of my virtual machines. I hope this works for you as well!

Solution 2:

just type: sudo apt-get install virtualbox-guest-additions-iso

Solution 3:

Install the latest version of virtualbox say 4.3.10 or above from here and also it's corresponding guest additions, extensions Or you can also install the latest virtualbox version from the multiverse repository via apt-get. I also faced the same problem in older virtualbox version running Ubuntu 14.04 as guest OS.

To install guest additions, follow this answer.

Solution 4:

If that happens once you have the guest additions installed, it may help reconfiguring DKMS

dpkg-reconfigure virtualbox-guest-dkms

It happens to me every time Kernel is upgraded and the above provides the solution.