
(SOLVED) VirtualBox Error 0x80004005: Failed to open session for VM
In this video, learn how to fix the VirtualBox Error 0x80004005, when you try to start a Windows 8.1 or a Windows 10 virtual machine:"
Duplicate config values '/CPUM/CMPXCHG16B' and '/CPUM/IsaExts/CMPXCHG16B' – please remove the former! (VERR_DUPLICATE)".
1. First, close VirtualBox Manager.
2. Start a Command Prompt as Administrator.
3. Type the following command and press Enter:
cd \Program Files\Oracle\VirtualBox
4. After that, excute the below command to list the VM Machines.
VBoxManage.exe list vms
5. From the output of the above command, remember the name of the VBOX machine, where you get the error 0x80004005.
e.g At our example, the VM machine with the "0x80004005" error, is the "Windows8.1_x64_Pro".
6. Next, type the following command, but replace the "VM-Your-Name" value, with the name of the VBOX machine that you face the error 0x80004005, and press Enter:*
VBoxManage.exe setextradata "VM-Your-Name" VBoxInternal/CPUM/CMPXCHG16B
e.g. At our example the command will be: VBoxManage.exe setextradata "Windows8.1_x64_Pro" VBoxInternal/CPUM/CMPXCHG16B
Now, try to launch the VM machine that has the problem.