I just came back from a long trip, from which I turned off my Vebatum Smartdisk 500gb network drive. Now for some reason I have been unable to access the network drive from the network and even if I hook it up to my macbook through USB. If I use the USB I can see it on the disk utility , but not on the desktop. From DiskUtility there are 3 partitions (responding to disk1,2 and three which are all unmountable, greyed out) These partitions house my music library. I tried Disk warrior to no avail, so I decided I would format and use a software recovery tool to get my files back.... Anyway, I erased using diskutility and now I have full usage of the hard drive, but I can only access 350 of the 500 gb.... The desktop drive that is listed, states 350 capacity, 350gb available....And diskutility lists the drive as having 350gb capacity without any partitions.

So my suspicion is that I had a permissions problem originally that I could not get passed. That's why I couldn't mount those partitions. I think when I erased the external hard drive, I only erased the blank data, and the previous partitions that I did not have permission to access were left unchanged..... but now I cannot view them, and have now acces to them- PLEASE HELP