In the sender, I have set the routing to epidemic, launched the daemon and typed 

dtnsend -g dtn://groupName/InboxReceiver <filename>

I have two other nodes that are configured with default routing.

As it is described here, https://mail.ibr.cs.tu-bs.de/pipermail/ibr-dtn/2014-January/000534.html

I launched their daemons and typed the command

dtnrecv --group dtn://groupName/InboxReceiver

But I did not received any bundle. Do I miss sth in the configuration?

Thanks in advance,

Best,

Theodoros