I recently installed Windows 10 (an upgrade from Win7), and I'm running into an issue where FSX will not actually start a flight unless I have the "Dx10 preview" option selected. If I don't have that option checked, FSX boots fine, but as soon as it finishes loading a flight, I get a black screen with the Windows "processing" circle, and nothing happens from there until I restart my PC.

 

I've updated my video drivers (a GTX 660Ti), tried downloading uiautomationcore.dll and putting that into the FSX folder, running FSX in Win Vista 7, and 8 compatibility modes, and am running FSX as the administrator, but it stubbornly refuses to start a flight running in DX9 mode.

 

Any ideas how to solve this aside from using the "I've made a huge mistake" option and just reverting to Win7?

Rename your fsx.cfg and let it rebuild another. FSX has different video settings for DX 9 an 10 so I suspect something was messed up in your DX 9 settings. Are you by chance using multiple screens? 

I forgot to put it in the original post, but I tried forcing a rebuild of the fsx.cfg several times, and it seems to have no effect on the hanging issue.

 

I'm running a single monitor.