Problem in dynamic memory allocation

[Parsa]

Hi there, i'm new to programming and i'm having a bit of a problem lately.
i'm writing a win32 windows application in microsoft visual c++ 2008, i have a class called Shape; in my main program i've declared a global pointer to Shape class like this:

Shape *shape = 0;

then in the middle of the program, when user clicks somewhere in the client area, i construct the object like so:

shape = new Shape(LOWORD(lParam),HIWORD(lParam));
shape->SetEnd(0,0);

then i compile it, there is no problem, but when the window starts an error message appear like this:

Unhandled exception at "..." in editor.exe: "some address here": Access violation writing location "some other address here"

Whats the problem,please help!
thanks a lot

[helios]

It's hard to tell with so little code.

[Parsa]

helios thanks for checkin out the thread. yea youre right.
i've simulated the same program with the exact same class in a console project and it worked properly. so i think the error is due to some settings for memory management n stuffs for windows projects or something. so the problem is not about the implementation of the class cause it worked in a console program with sample arguments sent to ctor and SetEnd function. is there any setting for the project which may be the problem here, about dynamic memory allocation and stuffs...?

[helios]

That kind of error can only happen when there's a problem in the code. Usually a buffer overflow, but any misuse of memory can trigger it.