I have a 2 TB external USB drive with two partitions: a small NTFS for Windows 7 and a large HFS for Snow Leopard. I have Windows 7 installed via Boot Camp with Macdrive. Both partitions seem to show up and work perfectly when I boot in Windows 7, but in SL, only the NTFS partition mounts. In disk utility, the HFS partition is greyed out and labeled 'disk1s1' (not what I named it) and says that it's formatted in 'MS-DOS (FAT)' format. When I try to repair the disk it says the following: "Invalid BS_impBoot in boot block: 000000 Volume repair complete. Updating boot support partitions for the volume as required. Error: Disk Utility can't repair this disk...disk, and restore your backed-up files." Considering neither of them are boot partitions, I'm not sure what the deal is. I tried running Testdisk to see if it could repair the partition map and it says "Write access is not available for this media, Testdisk won't be able to modify it". I have hundreds of gigs of data on this partition, so reformatting isn't an option. Any ideas? Thanks!