So, I was trying to do two things at once and it went badly:
I was just setting up a new HDD with Window7 on it, next to an old HDD with windows xp on it. I decided to shrink the XP drive and split it into tooto give both OS access to a common empty drive rather than have them accessing each others main partition. During the shrink process I disabled the Virtual disk manager which caused: "virtual disk manager the service cannot be started".
Now I have a 500Gb drive of which only 120 Gb is accessible. Disk management and EaseUs say the partition spans the whole drive and so I can't re-extend it. I really don't want to format the drive but I need access to the other 380 Gb!
Anyone else seen this before?