Came across this question while looking for my own mysterious
ERROR: unknown entry type 0xc1 running
FUSE exfat 1.2.7 which I could not really solve yet.
In my case everything seemed to work fine (AFAIK) until I mounted the exFAT-volume on a windows (8.1) system for the first time which mounted it without any complaint but showed an empty filesystem (no entries) but with some considerable space (about 66% which was about the amount of data copied onto it before on a linux machine) miraculously occupied.
I also found an issue on GH revolving around
unknown entry type 0x96 which started to let me think that the hex-code itself (
0xc1) is of minor importance, but something (not necessary the same) underlying went possibly wrong.
from the discussion on GH I learned that the following commands might help to get a clearer picture what might be going on (make sure to specify the correct device!):
mount.exfat-fuse -d /dev/sdb1
In my case, all these commands exited with the exact same error-message described above.
Also in the issue it is recommended to upgrade if running v1.1.0 as you are so that might already help in your case.
I yet have to take a closer look at what may have caused the corruption in my case as I have a suspicion that it might be related to the way I formatted the filesystem (
mkfs.exfat with individual volume-ID and name)...
EDIT: was able to reproduce what I wrote above. Certain characters in custom volume-names seem to cause the behaviour I observed. Issue #89 openend on GH ...
FUSE exfat 1.2.8 seems to successfully fix Issue #89 so I'd recommend to upgrade to that version (or newer once released in the future...).