preferences and key commands etc vanished!!

hi all,

using the latest cubase 6 very happily every day all day. all of a sudden today when i booted cubase i see it start scanning through everything as if its the first boot of cubase. finally boots, all key commands, preferences, window layouts etc, gone. WTF? i had a backup so its ok, just very surprised by this happening.

anybody else come across this? was it something i did to inadvertantly cause it?