I have been simming with FSX for many years on a Windows 7 machine and really enjoyed every moment. Recently I was forced to change to another computer, namely a Windows 8.1 machine that was available.

From that point on I have been taunted with Fatal Error crashes and started investigating why.

What I have done so far:-

1) Installed FSX to c:\FSX

2) Placed UiAutomationCore.dll in the installation directory

3) Placed highmemfix=1 in fsx.cfg

4) Run FSX in Administrator mode

None of these have fixed the problem.

Then came success.

I pressed ALT-ENTER so that I could get up the Windows task bar, to interactively save screenshots to other Windows applications of my progress.

By pressing ALT-ENTER, FSX now runs completely OK without any problems.

I hope this information might help somebody else who is screaming and shouting over this horrible Fatal Error crash problem.

Edited October 28, 20187 yr by eye_eye_captain
to continue

The AVSIM CTD Guide, page 34, FSUI.dll crash, is similar in that some have maximized their screen then shutdown windows.  When they restart, the sim will not load as there is a conflict in the FSX or P3D.cfg regarding the size of the screen.  I use to get it a lot but always try to shutdown in Windowed Mode and no more issues.

31 minutes ago, Jim Young said:

The AVSIM CTD Guide, page 34, FSUI.dll crash, is similar in that some have maximized their screen then shutdown windows.  When they restart, the sim will not load as there is a conflict in the FSX or P3D.cfg regarding the size of the screen.  I use to get it a lot but always try to shutdown in Windowed Mode and no more issues. 

Wow, that was a fast reply - thanks Jim.

Yes that exactly happened to me. I shut down and then could not load FSX and more. Thanks for your help and saving me endless sleepless nights.