[Edward.Fish]

I have a permanent window box, which I hide with my browser, insisting I upgrade. There is no little ‘x’ to close said box. It’s been there about 6 months now.

Try opening up Task Manager, see if you can see its icon on the Applications tab, if you can then right-click and end task. (You can use the "Switch To" button to confirm it if you're not sure.)

That said, it might not appear in the Applications tab.
You can also try Never10, but I haven't used it and so don't know how well it works.

[jpsb]

A freeper told me about Never10, I very cautiously used it. It worked great.