Disk Utility does not see used space of a partition

[Tex-Twil]

Hi,
I have a USB HFS formatted drive which is half full. When I open the Disk Utility it says that it is empty. When I get the info of the disk in Finder I get the correct usage.

Do you know what's wrong ?

 

[belvdr]

Highlight the volume, not the disk in Disk Utility

 

[RobertFord]

Highlight the volume, not the disk in Disk Utility

I think this is wrong. When you highlight a partition on the left you cannot select the "partition tab" anymore.

What Tex-Twil wants to see is this

 

[belvdr]

It was just a guess. Also since the partition is not GUID, it may not work at all.

 

[RobertFord]

What is a GUID ? EDIT: http://en.wikipedia.org/wiki/GUID_Partition_Table

How can one fromat a disk so that it is "GUID" ? Does it has to be bootable ?

r.