Ubuntu – I can’t find Install Guest additions option for virtualbox

Run

xrandr

You get similar to

Screen 0: minimum 320 x 200, current 800 x 600, maximum 1280 x 1280

VGA connected 800x600+0+0 (normal left inverted right x axis y axis) 376mm x 301mm
       1280x1024      60.0 +   75.0  
       1280x960       59.9  
       1152x864       75.0     74.8  
       1024x768       75.1     70.1     60.0  
       832x624        74.6  
       800x600        72.2*    75.0     60.3     56.2  
       640x480        75.0     72.8     66.7     60.0  
       720x400        70.1

    * item is current.

It is list of resolutions you can set. Now you can change by using

xrandr -s Index

index is number starting from 0 as the first line.

OR

xrandr -s widthxheight

Instead of installing the guest additions from virtualbox's virtual CD, you can try installing the pre-built Ubuntu package. Just:

sudo apt-get install virtualbox-guest-dkms

this will compile and install the required module and enable folder sharing, shared clipboards and resizable display with seamless pointer integration.

If you want to continue doing it the hard way:

1. The message on your screen clearly indicates a log file you can look at to get more details about the problem.

2. I'm pretty sure this is because you don't have the appropriate development tools and kernel headers installed. You can do this to install them, then retry your process:

   sudo apt-get install linux-headers-$(uname -r) build-essential