I think that this is something new, I've been googling for hours but the only mention I have seen that sounds like my variant (all solutions are for old varients that are seem to be completely different and ineffectual) is from 2 days ago.
http://www.bleepingcomputer.com/forums/topic341961.html
File retrieval is not an issue as I've got another OS on another drive but I really do need to save this particular installation and not just nuke it.