Or simply run sudo /media/$USER/VBox_GAs_6.0.14/n Installing Guest Additions ISO from Ubuntu Repositories Then navigate to the mount point of the guest additions and run the command below cd /media/$USER/VBox_GAs_6.0.14 Therefore press cancel when the installer dialog box opens up. Where x is the build version of VirtualBox. When the Guest Addition ISO file is inserted, it is mounted on /media/$USER/VBox_GAs_6.0.x. You can also install the Guest Additions from the terminal. Install Guest Additions Manually from Terminal You can as well restart your virtual machine to reload the Kernel modules. Press Enter to close the installation screen. Once the Guest Additions are installed, the screen automatically resizes itself. This will launch a dialog box which prompts you to run or cancel the Guest Additions installer. Once that is done, proceed to insert the Guest Additions ISO from the Menu bar > Devices. Sudo apt upgrade sudo apt install dkms linux-headers-$(uname -r) build-essential If none if these packages is installed, you can simply use the APT package manager to install them. As you can see from the output, dkms is not installed.

The ii means that the package is installed.

Ii linux-headers-5.3.0-18-generic 5.3.0-18.19 amd64 Linux kernel headers for version 5.3.0 on 64 bit x86 SMP sudo dpkg -l | grep -E 'dkms|linux-headers-$(uname -r)|build-essential' ii build-essential 12.8ubuntu1 amd64 Informational list of build-essential packages Run the command below to verify if these requirements have already been installed. However, before you can proceed with Guest Addition installation, you first need to install required build tools, the Linux kernel headers and the support modules, if not already installed. Note that before you can insert the ISO file, you need to have at least one empty IDE controller. To manually insert the VirtualBox Guest Additions ISO file on your Ubuntu 20.04 VM, navigate to Menu bar on your VM and click Devices > Insert Guest Additions CD image.

Install Guest Additions ISO Automatically from Ubuntu Repositories using APT package manager.Insert Guest Additions ISO File Manually.

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