[Spirit5676]

2019-01-12 10:42:19 INFO [T] ISTA: [1] ConfigSettings.ConfigSettings() - called
2019-01-12 10:42:19 INFO [T] ISTA: [1] ConfigSettings.StoreAndLogChangedValue() - Change configuration "BMW.Rheingold.OperationalMode" from "ISTA" to "ISTA_PLUS" (read from "Configuration file").
2019-01-12 10:42:19 INFO [T] ISTA: [1] ConfigSettings.ConfigSettings() - OperationalMode is ISTA_PLUS
2019-01-12 10:42:19 INFO [T] ISTA: [1] ConfigSettings.StoreAndLogChangedValue() - Change configuration "BMW.Rheingold.Logging.Directory" from "" to "..\..\..\Logs" (read from "Configuration file").
2019-01-12 10:42:20 ERROR [T] ISTA: [1] App.App() - Failed to start ISTA: System.TypeInitializationException: The type initializer for 'BMW.Rheingold.CoreFramework.CoreFramework' threw an exception. ---> System.DllNotFoundException: Unable to load DLL 'ISTAGUI.cfg': The specified module could not be found. (Exception from HRESULT: 0x8007007E)
  at BMW.Rheingold.CoreFramework.MSCoreEInterop.sEX(String wszFilePath, Boolean fForceVerification, Boolean& pfWasVerified)
  at BMW.Rheingold.CoreFramework.MSCoreEInterop.SNSignatureVerificationEx[T](Decimal resolution, Byte[] m)
  at BMW.Rheingold.CoreFramework.MSCoreEInterop.SNSignatureVerificationEx[T]()
  at BMW.Rheingold.CoreFramework.CoreFramework..cctor()
  --- End of inner exception stack trace ---

can anyone help me ?

Do you have ISTAGUI.cfg file?