I'd try this way: Backupmenu, option "w" that exposes the optfs to mass storage connect through usb to a linux machine now open terminal in your linux machine, become root, see what device corresponds to your optfs (I use the mount command without parameters which lists all the mounted partitions but I bet there are other better ways) - might be e.g. /dev/sdb2 or another Then in the same root terminal give umount /dev/sdb2 (of course use the name of your partition, here sdb2 is only an example) then fsck.ext3 -y /dev/sdb2 If you're particularly lucky it might heal your optfs. Then disconnect, reboot n900 and see if it worked. In case it doesn't, before you flash rootfs & eMMC, you could also reformat your optfs by connecting to a host computer like described above and using mkfs.ext3 after umounting instead of fsck'ing. If the partition table of your eMMC is not completely kaputt, it could save you the time to backup and restore your MyDocs partition. Of course, you'd have to reflash firmware in the same way, or restore rootfs and optfs from backupmenu in case you had a recent backup.