Oracle Virtual Box critical error NS_ERROR_FAILURE (0x80004005)

When opening Oracle Virtual VM I got the Critical Error below.

Failed to acquire the VirtualBox COM object.

The application will now terminate.

Document is empty.

Location: ‘…/.config/VirtualBox/VirtualBox.xml’, line 1 (0),
column 1.

(nsresult VirtualBox::init()).

Result Code: NS_ERROR_FAILURE (0x80004005) Component: VirtualBoxWrap
Interface: IVirtualBox {d0a0163f-e254-4e5b-a1f2-011cf991c38d} Callee:
IVirtualBoxClient {d2937a8e-cb8d-4382-90ba-b7da78a74573}

I encountered this issue when I deleted virtual machines while my solid state drive was full. I found out it was full because of the large amount of data I let timeshift take up…

After deleting some timeshift files and virtual machines and adjusting timeshift paramaters to prevent this from happening again; I found out that Oracle VM was not working. I reinstalled it and still had the same issue. I after searching online I found articles that said to reinstall and to restart the setup. I then noticed a few articles about deleting the VirtualBox folder in .config. I got to the .config by opening the terminal and typing cd .config . I then saw the VirtualBox folder and did a cd into that also. After listing the contents I saw lots of virtual machines I don’t have anymore and decided to just run a rm * on that folder to remove all the files.

I was able to open up Oracle and some files were restored that Oracle uses and now it works with no problem.

Did you check .config/VirtualBox/VirtualBox.xml? Does it have some content and is a vaild xml file?

Disable UBB 2/3 in Virtual machine settings before starting the machine.

Make sure you use the extension pack matching your virtualbox version.