When I tried to make a portable version of VirtualBox, when I use the launcher it doesn't work, giving an error saying it "failed to create a VirtualBox Client COM object", and then the application terminates. It seems the portable version was piggybacking off the non-portable installation I used to make it, as this error popped up when I uninstalled the non-portable version. How can I fix this?
You could download his GIT project and in his help/read file he explains which services need to start first and which drivers need to be initialized.
I have not done any active portable apps development in the last 9 month as such don't remember if you could do it directly of if you need to get dirty and code it manually.
P.S.: If it is not to much trouble, could you post your VirtualBox PortableApps files so that I can view them and see if I could help.