You seem to have asked this question and it was MARKED SOLVED about 3 months ago. Here
It isn't clear to me how you have a blank screen (not since the good old days before Windows). There is always the desk top even if you close or minimize everything else.
It is possible to minimize all other windows. You have to know their Windows handle and you need access to system calls. In other words it requires some APIs and a bit of code, (in other words it is easy to create unintended consequences) if that is what you want to do.
If that wasn't the answer then perhaps this will help:
If I understand, you want your program the only thing visible on the screen. If that means your program fills the whole screen then set the Form's WindowState to 2 "vbMaximized". Note: WindowsState is read/write with the following values: 0 (zero) Normal (re-sizable); 1 = minimized; and 3 = Maximized (not re-sizable).
You can also do this programatically in your Load event with the following:
Now i realise that we didn't understand there the real problem what OP wants to share.
As OP also soved the thread so we can't give time to solved thread as you know more question are there and waiting for appropriate answer.
we confused little bit there on the thread title Clear Screen And now i realise that it should be maximising the screen.