How To Fix The Error Unable To Insert The Virtual Optical Disk VBoxGuestAdditions.iso Into The Machine

After installing the virtual machine in VirtualBox, I want to change the virtual machine’s screen resolution in the virtual machine. So I click the VirtualBox Manager or Virtual Machine’s Devices —> Insert Guest Additions CD image… menu item.

But it shows the error message like Unable to insert the virtual optical disk C:\Program Files\Oracle\VirtualBox\VBoxGuestAdditions.iso into the machine macOS. This article will tell you how to fix it.

1. The Detailed Error Messages.

1. My virtual machine is macOS, so I get the below error message. If your virtual machine is Linux you will get the errors similar.

   Unable to insert the virtual optical disk C:\Program Files\Oracle\VirtualBox\VBoxGuestAdditions.iso into the machine macOS.
   
   Could not mount the media/drive 'C:\Program Files\Oracle\VirtualBox\VBoxGuestAdditions.iso' (VERR_PDM_MEDIA_LOCKED).
   
   Result Code: E_FAIL (0x80004005)
   Component: ConsoleWrap
   Interface: IConsole {872da645-4a9b-1727-bee2-5585105b9eed}
   Callee: IMachine {85632c68-b5bb-4316-a900-5eb28d3413df}

2. The Steps To Fix The Error Unable To Insert The Virtual Optical Disk VBoxGuestAdditions.iso Into The Machine.

1. Power off the macOS virtual machine.
2. Right-click the macOS virtual machine in the VirtualBox manager left panel.
3. Then click the Settings… menu item in the popup menu list.
4. Click the Storage item on the left side.
5. Then click the Adds optical drive. icon button on the right side.
6. In the popup macOS – Optical Disk Selector window, select the VBoxGuestAdditions.iso from the Attached list.
7. Click the OK button to save the selection.
8. Now start the macOS virtual machine, you will find the VBox_GAs optical disk on the desk.
9. Double click it to open it, and then double click the VBoxDarwinAdditions.pkg file to run it.
10. If the installation failed at the end, you may need to disable the macOS System Integrity Protection feature ( How To Turn On/Off SIP (System Integrity Protection) On Mac OS ).
11. And then run the below commands to enable the writing permission to the folder /System/Library/Extensions/.

    sudo mount -uw /
    
    sudo chown :admin /System/Library/Extensions/
    
    sudo chmod 775 /System/Library/Extensions/

12. And now you can install the VBox guest additions in the macOS virtual machine.

3. How To Fix The Error Unable To Insert The Virtual Optical Disk VBoxGuestAdditions.iso Into The Machine When The Virtual Machine OS Is Ubuntu.

1. If the virtual machine OS is Ubuntu, you can open a file explorer by clicking the Files icon on the left side.
2. Then you can find the VBox_GAs_6.1.32 iso file on the Files explorer left side.
3. Right-click the disk icon, then click the Properties menu item in the popup menu list to open the properties window.
4. Then you can get the disk saved directory in the popup window, the path is something like /media/jerry.
5. Go to the directory /media/jerry/VBox_GAs_6.1.32, we can find the file VBoxLinuxAdditions.run.

   /media/jerry/VBox_GAs_6.1.32$ ls -l
   total 47008
   -r--r--r-- 1 jerry jerry      763   20  2020 AUTORUN.INF
   -r-xr-xr-x 1 jerry jerry     6384   14 03:11 autorun.sh
   dr-xr-xr-x 2 jerry jerry      792   14 03:20 cert
   dr-xr-xr-x 2 jerry jerry     1824   14 03:20 NT3x
   dr-xr-xr-x 2 jerry jerry     2652   14 03:20 OS2
   -r-xr-xr-x 1 jerry jerry     4821   14 03:11 runasroot.sh
   -r--r--r-- 1 jerry jerry      592   14 03:20 TRANS.TBL
   -r--r--r-- 1 jerry jerry  4029558   14 03:17 VBoxDarwinAdditions.pkg
   -r-xr-xr-x 1 jerry jerry     3949   14 03:10 VBoxDarwinAdditionsUninstall.tool
   -r-xr-xr-x 1 jerry jerry  7474611   14 03:11 VBoxLinuxAdditions.run
   -r--r--r-- 1 jerry jerry  9439232   14 03:02 VBoxSolarisAdditions.pkg
   -r-xr-xr-x 1 jerry jerry 16895432   14 03:17 VBoxWindowsAdditions-amd64.exe
   -r-xr-xr-x 1 jerry jerry   270840   14 03:12 VBoxWindowsAdditions.exe
   -r-xr-xr-x 1 jerry jerry 10000520   14 03:13 VBoxWindowsAdditions-x86.exe
   -r--r--r-- 1 jerry jerry      259   4 23:48 windows11-bypass.reg
   

6. Run the file VBoxLinuxAdditions.run in the terminal like below.

   $ sudo ./VBoxLinuxAdditions.run 
   Verifying archive integrity... All good.
   Uncompressing VirtualBox 6.1.32 Guest Additions for Linux........
   VirtualBox Guest Additions installer
   Removing installed version 6.1.30 of VirtualBox Guest Additions...
   update-initramfs: Generating /boot/initrd.img-5.11.0-27-generic
   update-initramfs: Generating /boot/initrd.img-5.13.0-27-generic
   Copying additional installer modules ...
   Installing additional modules ...
   VirtualBox Guest Additions: Starting.
   VirtualBox Guest Additions: Building the VirtualBox Guest Additions kernel 
   modules.  This may take a while.
   VirtualBox Guest Additions: To build modules for other installed kernels, run
   VirtualBox Guest Additions:   /sbin/rcvboxadd quicksetup <version>
   VirtualBox Guest Additions: or
   VirtualBox Guest Additions:   /sbin/rcvboxadd quicksetup all
   VirtualBox Guest Additions: Building the modules for kernel 5.13.0-27-generic.
   update-initramfs: Generating /boot/initrd.img-5.13.0-27-generic
   VirtualBox Guest Additions: Running kernel modules will not be replaced until 
   the system is restarted
   

7. When you see the above output message that means the installation is successful.