Many people are getting the “No SDCard” error once flashing the Android “L” Developer Preview. The cause of this Android “L” seems to be pointing to a different location (data/media/0) than the past several Android iterations (storage/emulated/0).
No worries, there’s a simple solution. Once you have a terminal app installed and have successfully rooted your device just launch the terminal and type the following:
su restorecon -FR /data/media/0
That’s it! No more wiping System/Data, mounting and unmounting, flashing the userdata.img. I love simple fixes like this.