Get the Screen Coordinates?

[BlackAPI]

Hi everybody
Please help in this situation, I have an overridding function TextOutW , ExtTextOUtW but in those function coordinates are't screen coordinates a devicecontext coordinates, I want to retrive the screen coordinate so I used the ClientToScreen Function, it word well in application like notepad but in InternetExproler it did't word correctly, What is problem and how to correct it?

[kirants]

It is not clear what you are trying to fo. How does notepad and ie come into picture ?
Is your app trying to draw on windows created by other applications like notepad and ie ?

[BlackAPI]

They don't come into picture, I draw a fake(splash) form in a short time to force the current Window to redraw itself, my fake form is very small so not all current form redraws a only a part, where was my fake form.