Oracle VirtualBox has finally released version 5.2.22 which works properly with Windows 1809 or otherwise with the October 2018 version.
With the release of Update 1809 in October of Windows 10, Oracle's free VirtualBox program could not boot virtual machines, whether they were old or new.
IGuRu had it points out in a relevant article its from the first moment. But it took a whole month for Oracle to release a working version. So version 5.2.22 of VirtualBox is no longer a problem, so Windows 1809 users will need to upgrade.
Logically, if you run your VB, it will notify you of the existence of 5.2.22, so proceed to download and install it. If he does not notify you then download it from here.
The strange thing, however, is that in the meantime the people of Oracle released a version, 5.2, which solved earlier problems of the application but had no effect on the latest Windows 1809. It seems that this version was almost ready to appear and at the same time seeing that Windows 1809 had a failed appearance, with a bunch of problems causing their recall, so Oracle technicians went ahead with it, waiting for Windows to release a pre-release version.
However, those who had downloaded 1809 from the beginning waited a month to see the virtual machines work again.