How to Fix Could not open guest session: VERR_NOT_FOUND VirtualBox

Learn how to troubleshoot the "Could not open guest session: VERR_NOT_FOUND" error in VirtualBox with our comprehensive guide. Fix the issue quickly and get back to work!

VirtualBox is a popular and commonly used software for running multiple operating systems on a single machine. It allows users to create and run virtual machines, known as guests, on their computer. However, like any other software, VirtualBox also encounters errors and issues that can disrupt its smooth functioning. One such error that many users have reported is the 'Could not open guest session: VERR_NOT_FOUND VirtualBox' error.

This error occurs when a user tries to open a guest session in VirtualBox and is unable to do so due to the missing or corrupt Guest Additions. The Guest Additions is a set of drivers and utilities that enhance the performance and functionality of the virtual machine. In this article, we will discuss some effective solutions to fix the 'VERR_NOT_FOUND VirtualBox' error and get your guest session up and running again.

1. Check if 'VBoxGuestAdditions.iso' exists

The first thing to do when you encounter the 'VERR_NOT_FOUND VirtualBox' error is to check if the 'VBoxGuestAdditions.iso' file exists in your VirtualBox installation folder. This file contains the Guest Additions that are required for the smooth functioning of your virtual machine. If this file is missing or corrupt, it can result in the error. To check for the file, go to the VirtualBox installation folder, usually located in the 'C' drive, and look for the 'VBoxGuestAdditions.iso' file. If the file is missing, you can download it from the official VirtualBox website and install it.

2. Insert Guest Additions

If the 'VBoxGuestAdditions.iso' file exists in your VirtualBox installation folder, you can try inserting it manually into your virtual machine. To do this, start your virtual machine and go to the 'Devices' menu in the VirtualBox window. Then, select 'Insert Guest Additions CD image' option and follow the prompts to complete the installation. Once the installation is complete, restart your virtual machine and check if the error is resolved.

3. Upgrade Guest Additions

Another solution to fix the 'VERR_NOT_FOUND VirtualBox' error is to upgrade your Guest Additions to the latest version. To do this, go to the VirtualBox website and download the latest version of Guest Additions. Then, uninstall the current version of Guest Additions from your virtual machine and install the new version. This will replace any missing or corrupt files and may resolve the error.

4. Install VirtualBox Extension Package

In some cases, the 'VERR_NOT_FOUND VirtualBox' error may occur due to the absence of the VirtualBox Extension Package. This package contains additional features and functionalities for VirtualBox, including support for USB devices and remote desktop connection. To install the Extension Package, go to the VirtualBox website and download the appropriate version for your operating system. Then, open VirtualBox and go to the 'File' menu. Select 'Preferences' and go to the 'Extensions' tab. Click on the 'Add' button and select the downloaded Extension Package to install it.

The 'VERR_NOT_FOUND VirtualBox' error can be frustrating, especially if you rely on VirtualBox for your work. However, with the solutions mentioned above, you can resolve the error and get back to using your virtual machine without any hassle. It is also recommended to keep your VirtualBox and Guest Additions updated to avoid such errors in the future. If the error persists, you can seek help on the VirtualBox forums or contact their support team for further assistance.