How to fix the window resize problem with Ubuntu Linux in VirtualBox on Windows

This is a popular enough post, that I thought I'd reprint it here:

Oracle supports a free VM hypervisor called VirtualBox. I'm using version 4.3.28 on Windows 7. I want to put Linux on it. Ubuntu is one of the few Linux distros that offers an .iso image download. I download Ubuntu 14.04.02.

Out-of-the-box, the install comes with a problem. The display is too small, 640 x 480, to even see the entire display settings screen. There are no options for making it bigger, or for making it resize automatically.

Systems are so unbundled, dependency building is so unreliable, conflicts are so common, that it's unclear if my solution would work for even a slight variation on the above situation.

But here's my solution. When I found it, I deleted the virtual machine and tried the same installation procedure again, just to be certain.

1. install Ubuntu on the virtual machine
2. at the top of the VirtualBox guest operating system desktop window, click Devices->Insert Guest Additions CD Image …
3. you will be prompted to run the Ubuntu Guest Additions CD. Do it.
4. then shutdown from within the virtual desktop, and reset from the dashboard. Resizing should now work.

The dozen other solutions are probably just out-of-date. But, again, software distribution is in such a irresponsible state that it is not possible to know this for sure, without an extensive research initiative.