It is probably not possible to change the color when Visual Styles are on using normal Windows messages/functions.
There is a WM_CTLCOLORSCROLLBAR message but it only changes the background and does not work with most scrollbars:
The WM_CTLCOLORSCROLLBAR message is used only by child scroll bar controls. Scrollbars attached to a window (WS_SCROLL and WS_VSCROLL) do not generate this message. To customize the appearance of scrollbars attached to a window, use the flat scroll bar functions.
You can read about flat scrollbars @ https://msdn.microsoft.com/en-us/lib...(v=vs.85).aspx
but it is not going to give you the results you are looking for.
To actually get what you want you have to use the SkinnedControls_plug-in
or create a custom plug-in and do the drawing yourself, https://www.codeproject.com/Articles...ibrary-version
can probably help you out.