Return failing in a windows executable

I am using Microsoft Visual Studio to create a utility for firmware upgrade.
I am facing a very perplexing problem here.

printf("Before \n");
if(any_device_active()) 
stat=switchover(ni_handle,&SWover);
else return; <<<<--------Second ONE
printf("switch over stat =%d\n",stat);
Sleep(1000);
return; <<<<<---------Third ONE

As observed the first return is successful.
All the returns after that fail.
I don't seem to get the problem. I don't even know what to look for. Also by the way the switchover function is empty and just returns a 0. any_device_active just returns 0 and prints a list , no problem there. This is the error code the visual debugger throws 0xc0000409.

0xC0000409 is STATUS_STACK_BUFFER_OVERRUN: It means some write to a pointer overwrote something it shouldn't have on the stack, and the C Run-Time Library's security code in your function's epilog detected it.

You have some kind of buffer overflow bug or improper pointer use in your switchover() function.