FSX crashes running UIAutomationCore.dll.

This article is not applicable for Steam FSX-SE

Both files with different size…? 549Kb in C:/Windows/SysWOW64 and 734 Kb in C:/Windows/System32

uiautomationcore1Reading in different fora we came to the conclusion that this file UIAutomationCore.dll is causing FSX to crash and could be simply removed.

You should not remove the files when you have a crash in P3D.

How to remove UIAutomationCore.dll from windows 7? These multiple files are stored in C:/Windows/system32 and C:/Windows/Syswow64

Simply delete these files; make a spare copy in case of…

HERE IS THE FIX: You may have to take ownership of the files if windows stops you from deleting the file.
Open CMD prompt and right click to run as administrator and then type in exactly as below substituting your windows login username where it says username:

your username may not contain spaces! If so, make a new admin account]

  • takeown /f C:/Windows/System32/uiautomationcore.dll
  • cacls C:/Windows/System32/uiautomationcore.dll /G username:F
  • takeown /f C:Windows/Syswow64/uiautomationcore.dll
  • cacls C:/Windows/Syswow64/uiautomationcore.dll /G username:F

Now you can just navigate to your syswow64 and system32 folders in windows explorer and after backing up the UIautomationcore.dll files just delete them from your computer.
(Remember to delete the Uiautomationcore.dll file in your FSX folder also if you installed it as an earlier the fix. If you need this file anyway, please have a look in the download page).

Thanks to all the collaborators in

This is what you get in the command box:
take care that you use your own username!


Copyright (c) 2009 Microsoft Corporation. All rights reserved.

C:/Windows/system32 takeown /f  C:/Windows/System32/uiautomationcore.dll

SUCCESS: The file (or folder): “C:/Windows/System32/uiautomationcore.dll” now owned by user “JanV-PCJanV”.

C:Windowssystem32>cacls C:WindowsSystem32uiautomationcore.dll /G JanV:F

Are you sure (Y/N)?y

processed file: C:/WindowsS/ystem32/UIAutomationCore.dll

C:/Windows/system32 takeown /f C:/Windows/Syswow64/uiautomationcore.dll

SUCCESS: The file (or folder): “C:WindowsSyswow64uiautomationcore.dll” now owned by user “JanV-PCJanV”.

C:Windowssystem32>cacls C:WindowsSyswow64uiautomationcore.dll /G JanV:F

Are you sure (Y/N)?y

processed file: C:/Windows/Syswow64/UIAutomationCore.dll


type exit to close the command box
Go to the folders c:/windows/… to remove the files