Ytdyklly

I ran into this problem recently (Sept 2017) trying to install Guest Additions into Oracle VM VirtualBox Manager version 5.1.28, in a newly-installed VM for Ubuntu version 16.04.3. The host is Win-10. The problem was that the Guest Additions CD image was already mounted. To fix it:

• In the VM Manager under Settings->Storage, under Controller:
  Right-click on VBoxGuestAdditions, and select “Remove Attachment."
  There will be a confirmation box: click “remove.”


• Click the “+” icon next to “Controller," to add new optical drive. A
  dialog box will open. Choose “Leave Empty-> Okay”


• Open the VM and select Devices->Insert Guest Additions. It should
  install now. Power off the VM (not the VM Manager) and restart the
  VM. GuestAdditions should now be working.

For me, the solution was discovering that you have to add an Empty optical drive in the virtual machine settings! If you try to "help" by pre-loading the VBoxGuestAdditions.iso, it doesn't work. The shortcut on the Devices menu "Insert Guest Additions CD image ..." wants to find an empty optical drive to use!

Hi I was having same issue (copy and paste problem) and I entered following commands from terminal and solved the problem.

• sudo apt-get upgrade


• sudo apt-get install virtualbox-guest-additions-iso


• Go to display setting, under video capture, check enable video capture


• sudo apt-get install virtualbox-guest-utils


• restart virtual machine.

I had the same problem and manual installation with sudo apt-get didn't work for me. Different Virtual Box has different guests additions version so it's better to install the guest additions that comes with Virtual Box. So I installed it in this way:

1. From File manager choose "Devices" -> "Insert Guest Additions CD
   image..."


2. Login Ubuntu


3. Unmount the CD (guest addition cd image)


4. 
   

   Mount the guest additions iso

   
   
   

   It'll pop up a window asking for confirmation to run it or not. If choosing to run, enter the login password and install it.

   
   



5. Reboot Ubuntu

Got same error, get it work as below:

1. after got that error, unmount VBOXADDITIONS CD in ubuntu;


2. get out Ubuntu, click Devices - Insert Guest Additions CD Image. This time it will pop up a window asking run it or not,
   
   
   
   
   • choose to run
   
   
   • enter the login password
   
   
   • start to install now.
   
   
   
   

The problem many times that happens is that the iso file you installed is already mounted. Just go to Devices-Optical Device-Remove Virtual Disk from Guest installation. Then Manually mount the Guestadditions.iso file by going to Devices-Optical Drive-Choose Disk image then go to the folder where you installed ubuntu, find the guestadditions.iso file and then mount it. Once mounted, simply again click the Devices-Install Guest additions, enter your userID password for Ubuntu and the wizard will then continue to install the guest additions :)

In my case this happened because I was running Ubuntu server which doesn't have a window manager. Here is how I installed:

First, boot up the Ubuntu VM. Then press Devices > Insert Guest Additions CD. The CD has now inserted but you won't see anything. If you try to press Insert Guest Additions CD again you will get the error.

Next mount the CD:

sudo mount sr0 /media/cdrom

And then cd into the directory (no pun):

cd /media/cdrom

Next, run the install script:

sudo ./VBoxLinuxAdditions.run

And now everything should fine :)

I had problems that after mounting ISO the disk was empty in Debian. I made following workaround:

1. mount addons image in Deamon tools in home Win system


2. copy files from iso to shared folder to access them from virtual Debian


3. perform SH installation directly in that folder (you will have access to addons files all the time via this folder)

Same error for me with Macos. I was hitting the error Could not mount the media/drive '/Applications/VirtualBox.app/Contents/MacOS/VBoxGuestAdditions.iso' (VERR_PDM_MEDIA_LOCKED). The guest additions iso was already downloaded previously. All steps are done within VM.

1. cd to media/<user>/Vbox_GAs_<version> (there may be multiple folders here so choose the most recent).


2. 
   ./autorun.sh to install the guest additions iso


3. sudo reboot

I solved by manually mounting the image (after adding the Device and the ISO according to the Dave Rose's answer) and running the installer.

sudo su

cd /media

mkdir cdrom

mount /dev/cdrom /media/cdrom

cd cdrom

sh VBoxLinuxAdditions.run

Check my answer on SuperUser 😉