It seems that my wbfs-formatted partition of my external HDD is damaged.
Win 10 "mounts" it and assign a drive letter but when trying to access it via Wii Backup Manager the log file say:
Not a valid filesystem but could be WBFS - H (drive letter)
Invalid partition header - Not a WBFS...
I discovered today a strange thing regarding compatibility on new3DS.
Emulators, which work fine on old 3DS XL (latest FW) does not run 100% on new3DS XL (sysnand FW 9.0). The touchscreen does not recognize inputs.
I have tested with my SuperCard DSTWO latest versions of Stella DS, nes DS...