Thanks for answering. I've been clicking on the GPS530 in the panel but it doesn't come back in either the C172 or Baron 58 since it was minimized.
I copied the X-Plane Window Positions.prf file then deleted the original and restarted X-Plane but the 530 pop-up still doesn't appear. The 430 works OK.
I had a similar problem with my Epson scanner s/w where the preview screen wouldn't show up. I finally found it by switching to a single screen resolution.
So I tried running X-plane on a single screen and with two screens active but still no luck. I also clicked around the window edges to see if it was just off screen.
It's not a big deal since the 530 still works in the panel and clicking from the 4th monitor to the main screen causes it to blank then redraw over a few seconds.
But it's handy in FSX to store the GPS, ATC, kneeboard, etc. on the 4th screen. Are there other preference files I should try? I'd rather not have to reset all my
yoke, pedal, and quadrant settings. Thanks again.
Clark