Thanks for your answers!
Yesterday i tried it like the pdf "Guide to debricking Kindle Touch" and when i want to copy the main partion with dd if=/mnt/us/mmcblk0p1.img of=/dev/mmcblk0p1 bs=4K i got dd: can't open '/mnt/us/mmcblk0p1.img': No such file or directory
What am I doing wrong? I copied the file "mmcblk0p1.img" an the kindle root with explorer.
Can you give me a step to step guide what is the problem and the solution for it?