I have a laptop which I run the main Poser program and an external monitor which has my Libraries, Animation Controls, Editing Tools and the Hierarchy Editor on. I've always run the monitor above the laptop screen. No problems there.

Now, I've had to move desks which means I have to have the monitor beside my laptop so the screens are now side by side not one above the other. Still, no problems, all set up. But, there's always a but, my Poser libraries now insist on launching directly over the top of my main Poser program. The other items, the Editing Tools etc all launch on the monitor where they used to before the change.  Anyone know how I can force the Libraries back onto my monitor at start-up?

It's not really a problem but it would be nice to get the layout to stay where I want it.

I've tried resetting to Factory but that didn't work.

I have not been able to figure this out. I have two monitors and a drawing tablet attached to my computer. Poser insists on popping menu palettes up on the tablet. Even if it's not on. Even though I've never placed any part of Poser on the tablet.

I've tried all kinds of things, but nothing fixes it.

Until you find the reason why your library windows insists with its non-desired location, I'd like to suggest you to use this:

My Poser windows are dispatched on two screens, with slightly different setups in each room. This tools saved my life more than once 

Did you try set "launch to preferred scene"?

Heh, yes, I tried all the options provided by Poser but nothing worked. I am wondering if it's something to do with Adobe Air though as all the other items that I want open are part of Poser. The libraries are the only ones using something external. 

I've cured my problem for now, I've put them back to one above the other. I just removed the shelf that was in the way that the shared printer sat on and chucked it into a cupboard. Well, its always going wrong anyway!