commands to reinstall Guest Additions You need to place the .iso file via VirtualBox GUI

installGuestAdditions.sh

#!/bin/bash
 
###
# 
# Copyright (c) 2013 KimSia Sim
# 
# Ubuntu 13.04 vm to reinstall the Guest Additions
#
# partly inspired by https://github.com/fespinoza/checklist_and_guides/wiki/Creating-a-vagrant-base-box-for-ubuntu-12.04-32bit-server
#
# Run this by executing the following from a fresh install of Ubuntu guest VM:
# 
#     bash -c "$(curl -fsSL https://raw.github.com/gist/5727446)" 
# 
# Be sure to replace <webapp.com> with your intended webapp name.
# Also, run this as root, unless you enjoy failing.
# 
###

sudo apt-get install linux-headers-$(uname -r) build-essential
mkdir /media/cdrom
mount /dev/cdrom /media/cdrom
sudo sh /media/cdrom/VBoxLinuxAdditions.run