Originally Posted by montalex
when you restart after update, you'll see the usual boy under tree image, then the screen will flash, and you'll get the same imagine with the loading bar. After about 20% progress, the Duokan screen boot screen will flash. It is only there for a few seconds, so be ready to press Q (Kindle3) or 1 (Kindle2).
I reset to default my kindle, uninstalled jailbrake and screensaver, then installed duokan and reinstalled jailbrake and screeensaver: now it works!