Boot Camp Missing Partition Problem

Alright. Long time lurker on the main page, first time problem poster.

I installed Windows 7 on Boot Camp and Parallels a long time ago. Since I got my Mac.

I'm trying to access it today but my partition seems to be missing. I am missing 80 GB (my partition) so I know its still there but I can't boot into Windows and in Parallels, it tells me that it can't find the hard disk.

I see this thread but I don't think its the same problem and I'm not sure where to go from here.

Any and all help would be massively appreciated ASAP.

 

It reappeared for a second for some reason but going into parallels and starting caused it to disappear. It has never done this before obviously.

EDIT: It's there again but then it disappears. And parallels doesn't seem to work now.