Hello Marini,
If the problem is IIS stops working and can't send data through DI API then there may be an exception you forgot to handle. If your IIS applications are throwing an unhandled exception at some point it will cause application to stop. Could you check your code and see if there is a part outside of Try/Catch block which may throw an exception.
Also to find the root cause I can suggest you to run your IIS application project via Visual Studio then add the generated link to another visual studio project and debug it.
Thanks,
Atilla
Message was edited by: Atilla Aykut Genç