Main Window incorrectly stretches across two screens

[Tangmere_Museum]

The Tangmere Military Aviation Museum's English Electric Lightning flight simulator has developed a display problem since upgrading to P3D v5. The setup (shown in the image below) is for the main window to show the cockpit view projected at 1280 x 800 by a Sony PWZ10 while a second window displays the flight instruments on a 14" monitor at 1024 x 768.



This setup has been running on the same computer/graphics card for the past 5 years with various versions of P3D without problem until an upgrade to V5. Now, on startup in the morning, the program boots with the main window stretched across both screens with the right side of the main view hidden behind the instrument panel display as shown below.



This renders the simulator unusable until I or one of my colleagues can get to the museum to reset the displays. Once this has been done, the displays continue to show the correct layout for the rest of the day (a CTRL+; reset is sent after each 15 minute flight) but after shutdown at the end of the day, the simulator restarts the next morning with the same stretched main view. To try to cure the problem I completely uninstalled v5.1 hotfix and rebuilt the simulator from scratch with a full install of V5.2 hotfix but the problem persists.

Any help with this problem gratefully received.

TM

Software:
Prepar3d Professional v5.2 hotfix1, ORBX True Earth Greta Britain South (commercial licence), Tangmere airfield scenery (made in-house), Just Flight English Electric Lightning, FSUIPC, Windows 10.

Hardware:
Computer - Intel 6th Gen Quad Core I7 6700K 4.0GHz, MSI GTX 980 TI GAMING 6GB GDDR5, 16GB (2x8GB) DDR4 PC4-21300 2666MHz Dual Channel, Samsung 850 EVO SATA 6Gb/s 2.5" 500GB SSD.
Projector - Sony PWZ10 running at 1280 x 800 (native res)
Second screen - 14" vga monitor running at 1024 x 768.

[Rob McCarthy]

Hello,

If you exit full screen and re-save the scenario does it fix the issue? Also are you only seeing this I'm full screen?

Regards,
Rob McCarthy

[Tangmere_Museum]

It only runs in full screen so I can't say whether or not it would happen outside that mode. When it does happen, I exit full screen to realign the window and then return it to full screen. At first, I did resave the scenario after each realign but, as this did not prevent the problem happening after the next overnight shutdown and morning startup, I no longer do so.

TM

[Tangmere_Museum]

Oh dear, two months since posting and still no constructive help from Lockheed Martin. I didn't expect a quick answer - sniper21 posted about a similar problem back in April and didn't get a single response until I posted in August and he still hasn't had a sensible answer - but surely it's not too much to expect a little bit of help LM?

TM

[alaxus]

How are the monitors set up in Windows? Left to right or up and over?
You can change the setup in Screen Resolution.
Drag the second monitor under the first. Don't know what it will do but it's worth a try. I had a similar sim setup like yours and used the monitor top and bottom rather than left and right.