The newest build for VirtualBox is 4.2.4 and it is a maintenance release, designed to improve overall stability of the application as well as functionality.
Among the repairs available in this revision there is a regression from version 4.2.2. It would issue a warning that indicated that the value of the host file on the proxy page was invalid; however, this would appear despite the fact that proxy would not be enabled.
Another regression bug that has been eliminated in this revision is BIOS related and refers to broken DMI information. On the same note, the developer introduced a workaround for booting from Windows 2000 floppy disks.
Additional changes touch on storage component, which would hang under rare circumstances and VRDP component, which would crash some times during video playback in the guest system.
The full release log can be found on this page.
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