RegisterClassEx gives fails as error code 87 (Invalid Parameter)

this is my code:

Code:

WNDCLASSEX wc;
wc.cbSize = sizeof(WNDCLASSEX);
wc.style = NULL;
wc.lpfnWndProc = WindowProcedurepopup;
wc.cbClsExtra = NULL;
wc.hInstance = Instancepopup;
wc.hIcon = LoadIcon (NULL, IDI_APPLICATION);
wc.hCursor = LoadCursor (NULL, IDC_ARROW);
wc.hbrBackground = (HBRUSH)(COLOR_BTNFACE+1);
wc.lpszMenuName = NULL;
wc.lpszClassName = Classnamestring;
wc.hIconSm = LoadIcon (NULL, IDI_APPLICATION);
RegisterClassEx (&wc)

it is created for use in a popup window. Do you see what is wrong or is it possible to create a popup window without using this class?

Joossie4

My first guess is that you have not set a style for the window.

Code:

wc.style = NULL;

Error 87 from RegisterClassEx()

Also, you are leaving cbWndExtra in an uninitialized state.

Originally Posted by manasij7479

Error 87 from RegisterClassEx()

I had posted it as well but in this case hIconSm has been initialized.

Originally Posted by _Mike

Also, you are leaving cbWndExtra in an uninitialized state.

thanks

Originally Posted by joossie4

this doesn't matter, if i use "wc.style = CS_DBLCLKS;" it still doesn't work.


in my main window it is also initialized as NULL and that does work

So you have 2 window classes? You are not using the same class name for both are you?

i do have two window classes, is that not good? if that is good should i have a second window procedure and a second HINSTANCE?