What you are seeing are both the same disk.
Macintosh HD is the name that appears on the desktop and ST98823A is the actual drive. It would appear to be a Seagate drive.
The 74.5GB is the size after formatting, you did not loose anything, it is just a different way of measuring capacity.
Boot Camp believes that you have two partitions already. How many disks appear on the desktop?
P
I am trying to use boot camp on my Macbook and I keep getting this message when it tries to partition the hard drive:
"Back up the disk and use Disk Utility to format the disk as a single Mac OS Extended (Journaled) volume. Restore your information to the disk and try using Boot Camp Assistant again."
I read on another thread that this was because my hard drive is already partitioned? So I opened disk utility and I have these two drives:
Macintosh HD and "74.5 GB ST98823AS Media"
What is that second partition?? It says it is "read/write" and "GUID Partition table" at the bottom. it doesnt say that there are any files or available space on it. I have an 80 GB harddrive, which all shows up under the Macintosh HD section.

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