Was it spanned?
Was this disk spanned with another disk? Or is just a single hard drive?
Possible solution by dynamic disk convert software
Yeah, Was this disk spanned with another disk? Or is just a single hard drive? And what is your operating system? Have you moved the disk from other place? if you moved the disk you may destroy the disk configuration and maybe you could not retrieve your data. I know some problem may cause this, like you remove the disk from other place, you may encounter this problem, to solve this problem you could indirectly convert it back to basic, like this software http://www.dynamic-disk-converter.com it is tool that could recognize invalid dynamic disk and then use method like clone it to the other healthy place. You could have a try it is data protective,