Good question.
By default, a socket based receiver in QIE expects a block header and block footer. This allows HL7 messages to be sent with minimal overhead and still know where to start and stop a single message.
To connect to a listening channel with Telnet, I had to turn on my Telnet Client and Telnet Server:

Without the Telnet Server checked, I get the following error:
Connecting To localhost...Could not open connection to the host, on port 4556: Connect failed
I can connect to a channel via telnet, but it is not very helpful in sending a message unless I send a block header and footer.
