As I said we will meet again
Today I had my problem again. Explorer was hidden.
A while ago I wrote a program that shows the explorer directory name although
explorer was HIDDEN. So I had an indication.
Searching again for an answer I found a solution.
https://stackoverflow.com/questions/12946150/how-to-bring-my-application-to-the-front
I added
SetWindowPos(WebBrowserApp.HWnd, HWND_NOTOPMOST,0,0,0,0, SWP_NOMOVE or SWP_NOSIZE);
SetWindowPos(WebBrowserApp.HWnd, HWND_TOPMOST,0,0,0,0, SWP_NOMOVE or SWP_NOSIZE);
SetWindowPos(WebBrowserApp.HWnd, HWND_NOTOPMOST,0,0,0,0, SWP_SHOWWINDOW or SWP_NOMOVE or SWP_NOSIZE);
and it worked. It poped up explorer.
Thanks again