I was recently installing a trial version of SBS 2008 on a Sun Virtual Box (now Oracle Virtual Box) when I got a very non-descriptive error during the first few seconds – the installer would say “Windows is loading files” and then throw an unkown error 0xc0000225. It turns out the reason was that I had configured the box with less than the minimum memory – the minimum is 4 GB and I had it set with 512 MB (I know, stingy, but hey, it was a test!)