I'm stuck in the same situation. I upgraded from Itools 1.75 (UDE2) to latest version of NkPatcher and I ran into the same problem. The data is there based on the amount of free space left on the F: drive, but I cannot see it. I reformatted the other drives so I could start with a "clean slate" but keep my games. Still trying to figure this one out. If all else fails, I'm going back to my original setup. At least now I know that reformatting F: may not help. Hopefully I'll be able to get my F: drive data back somehow...
I need help with my Softmoded 1.6v Xbox with a Samsung 160GB HD.
Before I installed the new Exploits GameSave Softmod from Krayzie (v2.

, on my Xbox was another old Exploits GameSave Softmod installed. I overwrote thisone an everything looks fine.
Then I tried to open some Movies with the Xbox Media Center of the F: Drive, but there was nothing to find. The Drive had the same free space as before, so the Data was allready on the Drive but not read- or seeable. In the Krayzie Softmodtool, with has FTP-Server too, all the Data was seeable. So I save all my Data an my PC, and formated the Drive with the Softmod-Tool again (the F-Drive).
Then I started the MediaCenter again, and copied the Data back on the Xbox F-Drive. First I thought all works correctly, but when I restarted my Xbox, all the Data was unsee- or unreadable again.
Please help me with this strange Problem. THX.