Debug is going to Startup.s instead of main.c

Hello, i am new to uKeil and trying to learn how to use the software. I am trying to run a simple code which simply increases the variable value. When i start debug it always goes to the startup.s file and i cant able to step over or do anything in the main.c file 

Any code i am trying to run has the same behavior it stuck at  B __main 

I am using "LM4F120H5QR" as my device ; compiler -->  default version 6; in debug tab I am using simulator;  

i am tried different things that were suggested in this form, but i cant able to fix the problem. Can some one help me with this issue 

Thanks in advance