DialogBox() fails on Vista if parent hwnd is an external process window handle   

Hello,

I am developing COM object, and one of the methods shall display
dialog box:

STDMETHODIMP Xxx::InvokeUI(/*[in]*/ HWND hwndParent)
{
	DialogBox(g_hDllInstance, MAKEINTRESOURCE(IDD_XXX_SETTINGS),
hwndParent, (DLGPROC)XxxDialogProc);
	...
}

The hwndParent param is a window handle provided by external
application. In this case DialogBox fails with 'Access Denied' error.
But if null is specified as dialog's parent window, dialog box is
successfully displayed.

As per Vista requirements, application to have access to external
window handles, must:
1. have manifest with uiAccess parameter set to true
2. be Authenticode signed
3. resides in a protected location

All this requirements are met.

What is wrong?

Thanks,
Maxim.

date: Thu, 17 Jul 2008 04:06:05 -0700 (PDT)   author:   unknown

Re: DialogBox() fails on Vista if parent hwnd is an external process window handle   

Fixed.

Additional registration keys is required for COM objects to avoid UAC
penalties:
http://weblogs.asp.net/kennykerr/archive/2006/09/29/Windows-Vista-for-Developers-_1320_-Part-4-_1320_-User-Account-Control.aspx.

date: Fri, 18 Jul 2008 09:25:17 -0700 (PDT)   author:   unknown