Error Code: AutomationTool was unable to run successfully. Exited with code: 134

Hey,
after at the end of rendering/packaging (at least I hope it is the end) I get the errror : LogPlayLevel: Error: RunUAT ERROR: AutomationTool was unable to run successfully. Exited with code: 134
PackagingResults: Error: Launch failed! Unknown Error .
Do you have any idea how to solve the error?