Refer: https://forums.virtualbox.org/viewtopic.php?f=6&t=75068
These are the steps that VirtualBox takes when it writes a new Vbox file. Each step is contingent on the last one being completed without errors.
- Make a backup of the temporary file with ".vbox-tmp" extension.
- Delete any existing ".vbox-prev" file or change it to -BAK001 extension
- Rename existing ".vbox" file to ".vbox-prev".
- Rename ".vbox-tmp" to ".vbox"
Refer: https://www.techprevue.com/virtualbox-inaccessible-file-not-found/
iii) Out of the above-mentioned issues, "File not found" is the most common one. During that situation, you can go to the location of the file. One of the possibilities is that you might find suffixes after the extension .xml for eg. .xmlmog or .xmlemf. So if you are looking for file abcd.xml it actually exists there by name abcd.xmlemf and hence your system was unable to find the file abcd.xml because it did not exist. Now what you can do is, simply copy the file and paste it in the same location and rename it with extension just .xml. This would solve the issue of an inaccessible "file not found" error.