can't control a window

[Usama Akkad]

Hello,
I liked RealVNC very much because it's open source and it works.

I had a little problem with some windows. it seems that the pointer can't
get over the window so I can't move, drag and drop, or click any button on
it.

a screen shot is attached. it maybe a security feature of Kasper anti-virus
but I'm not sure.

Every other windows I tried is working

Best Wishes
U.A