Windows communication foundation - WCF - is the way to usually communicate between tiers with MDriven technology.

WCF can be tricky since it is rather silent when it fails.

So if you have ruled out other issues and you still cannot get the communication to work turn on WCF-logging.

In most web.config we have left a commented block to turn on WCF-logging.

This is from the MDrivenServer:

You can find more info here:

https://www.capableobjects.com/2011/06/26/wcf-and-eco/

https://www.capableobjects.com/2012/01/06/wcf-trouble-shoot/