I have a Win10 Enterprise Edition 2016 PC connected to two TVs. It replaces a Win7 Enteprise Edition TV that was connected to the same TVs in the same orientation. The TVs are each in portrait orientation with their top bezels touching (to minimize gap between the screens), so the left (primary) screen is in "Portrait" mode and the right (secondary) screen is in "Portrait (flipped)" mode. UltraVNC is set to show the secondary display.
When the PC is not logged in, the screens display properly, but when it is logged in, the resolution of the VNC window and mouse location are each correct, but after displaying correctly for a brief period (seconds at most [after login or reconnect from UVNC]), the pictures turn sideways and overlap each other at the top of the window instead of being in the proper orientation and correct portion of the window.
I can not state for certain that this issue is or isn't version or configuration specific, because I'm not sure what version was installed on the Win7 machine, but I can state that I am using version 220.127.116.11 in when I see this issue. I can also state that I don't see this issue when using the same version and configuration on other Win10 Enterprise Edition 2016 PCs where there are multiple displays with higher resolutions that are not rotated.
Restarting the service or the PC does not change the behavior. Any suggestions on what I can do to try to resolve this?
ETA: Sorry for the duplicate (now deleted) post, missed the moderation notice and thought I had answered the spam blocker wrong.