Reinstalling only apps without reformatting all disk

[sibe]

Hello all,

After a failed update, my HDX900 does not see any more the applications, and my only choice is to reformat completely to reinstall the applications (no update option available). I tried to put the disk into my linux box, and to do an e2fsck, which didn't find any errors. Then I copied over the nmt8634 folder (following Lundman wiki, "dd if=syb8634.nmt skip=1 bs=60 | tar -xzvf -" ). But without results. There are 3 partitions, the first one with apps (but seems something is missing, I have only lost&found and syb8634 folder), a swap partition and the third partition with all my datas. Datas are accessible, without any problems, the disk is well seen as a media (Hard_Disk_A3 instead Hard_Disk)), so I search how to reinstall apps partition without reformatting data partition.

What should be in apps partition to be seen by the firmware ?

Thanks for any answer or link !