I’ve noticed quite a few times that after a while using SQLNav, there appears a little square thingy in the top left corner of my desktop (Windows XP Professional 64-bit, BTW) - see first screenshot.
It’s an actual window, that can be expanded by clicking and dragging the lower right corner (not much to click on, practice your aim!) - see second screenshot.
This window seem to belong to the “Knowledge Expert Engine” (that’s what Process Exporer tells me anyway), but closing it does not seem to stop this or any other process.
I think (but am not sure) that this window appears after double-clicking on an Oracle error message in the output window (to bring up the Oracle Error Information dialog).