Originally Posted by pportnawak
I didn't ask the Amazon support team.
After reading the answer of a reboot. ... I just realised that i had duokan installed on my kindle.
I deleted it and restarted.
I can now open all my books without having to reformat everything.
I copied the folders of duokan back and evrything is back in order.
Thank for the hint geekmaster and ixtab ... i overlooked the dual boot. Sorry about that.
Gee, that's something easy to forget that you've done to your Kindle. Oops I had installed an alternative interface to dual boot to but I totally forgot and blamed Amazon's firmware for my problems.