But did you create the vfat partition in Knoppix? I'd be inclined to back up all your important data and reformat that partition through Windows.The data partition is also in FAT 32 and so windows should be able to see it.
I have 3 partitions in my HD knoppix, windows xp and a data partition. When I did a HD install of Knoppix,i was able to see all partitions. However, when i rebooted to windows, the data partion cannot be found. I know the partition still exists since I can see it in knoppix and the boot loader shows it as a windows partition ()i tried booting it but no luck since there was no OS just data) The data partition is also in FAT 32 and so windows should be able to see it.
But did you create the vfat partition in Knoppix? I'd be inclined to back up all your important data and reformat that partition through Windows.The data partition is also in FAT 32 and so windows should be able to see it.
Check using cfdisk that it is 'vfat' and not 'vfat hidden'. QTparted seems to make vfat hidden at times.

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