I found a folder named lock_map not lock_maps, any way I renamed it and maps worked again.
It seems really corrupted as I show folder details it show size of a 24 GB where the E: is only 8 GB.
Please Nokia go forward, you are breaking our hearts.
there is no folder called cities on my phone . what can I do ???
Either E:\cities or F:\cities is created once you open Nokia Maps application.