If it contains something like
This is due to the fact that the UIAutomation.dll that is being tried to load does match your System-Archtecture (64 vs. 32 bit).The type initializer for 'System.Windows.Automation.Peers.AutomationPeer' threw an exception. ---> System.TypeInitializationException: The type initializer for 'System.Windows.Automation.InvokePatternIdentifiers' threw an exception. ---> System.BadImageFormatException
Most likely you installed a custom UIAutomation.dll on your system to make FSX/P3D work on 64bit, and installed that dll in the system and did not just copy it to the FSX/P3D Directory.
Most likely because you installed a custom UIAutomation.dll.
First you should try the repair-function of the .Net Framework 4.5 in System Control Center -> Add/Remove Programs
If that does not help, try copying the UIAutomation.dll from your FSX/P3D Directory to the main Directory of SPAD.neXt.
You can also install the required UIAutomation.dll gathered from the Microsoft page: https://support.microsoft.com/en-us/kb/971513