Hello, I will ask Keil tomorrow, but have you noticed that you can build your FlashFS application using Microlib, 'finit' will return "OK", but 'fopen' will fail? I have spend 9 hours today dismantling Keil's stuff until a small prototype (RTX + FlashFS) revealed this grim reality... I did not see any reference to that in the documentation, even though somebody here talked about it (I just recalled that)...