Thread: GetSaveFileName exception

I don't mean to annoy the readers, but I need some help with an exception problem with the function (I'm sure a lot of you have used this function, but I'm still inexperienced with it). Below is my code:

Code:

BOOL AskUser(IN HWND hDlg, 
			 OUT PEXTDEVMODE pdevmode)
{
	OPENFILENAME fn;

	// initialize OPENFILENAME structure
	ZeroMemory(&fn, sizeof(fn));

	fn.lStructSize = sizeof(OPENFILENAME);
	fn.Flags = OFN_HIDEREADONLY;
	fn.lpstrTitle = L"PDF SaveFile";
	fn.hwndOwner = NULL;

	// ???
	fn.lpstrCustomFilter = NULL;
	fn.nMaxCustFilter = 0;

	// output format
	fn.lpstrFilter = L"*.pdf";
	fn.nFilterIndex = 0; //formatIdx+1;     // the index here is not zero-based

	// output file name + path + ext
	fn.lpstrFile = L"";
	fn.nMaxFile = 1000;

	// output file name + ext
	fn.lpstrFileTitle = L"";
	fn.nMaxFileTitle = 500;

	// output folder
	fn.lpstrInitialDir = NULL;

	GetSaveFileName(&fn);

	return TRUE;
}

I'm getting exception errors at run-time after I have pressed "OK" button on the Save File dialog box.

Code:

First-chance exception at 0x763b1ff8 (comdlg32.dll) in Savefile.exe: 0xC0000005: Access violation writing location 0x0041597c.
Unhandled exception at 0x763b1ff8 (comdlg32.dll) in Savefile.exe: 0xC0000005: Access violation writing location 0x0041597c.

After searching through the forum, there's a similar problem with an exception getting thrown (http://cboard.cprogramming.com/showt...Name+exception). However, I'm not sure 100% if this is the case. I'm not sure what is fundamentally wrong with how I've set up the openfilename structure as I have attempted to follow MSDN documentation as diligently as I could. The next step for me perhaps would be using a debugger such as windbg or Visual Studio debugger to look at the register values to get some clue about the exception, but I'm not sure how to make sense out of it. Any suggestions would be much appreciated. Thanks in advance.

No, I haven't included a filepath. I have the user specify the filepath, and the parameter being passed is acting both as an input and output.

Thanks for all your advices. After following your advices and rereading the documentation and more sample code, I have managed to achieve what I wanted to do to retrieve the filepath.