I have a named instance on a SQL 2012 Express server that won't connect via TCP/IP when wanting to connect off of the dynamic port.  I can connect via shared memory locally on the server.   I can connect to the namespace when specifying the dynamic port listed in the configuration manager.  

This is the only named instance on the server and it is not the default.
TCP/IP is enabled
Allow Remote connections is enabled
the server browser service is running
I can connect via the dynamic port number

I am testing the connection locally on the server, so I don't believe a firewall is the issue.  I get the same results if I test it from a remote computer.

When using the sqlcmd (sqlcmd -S tcp:SQLSRVR\NAMEINST -E) I get the message that "the requested protocol isn't supported [xfffffffff]".   The command (sqlcmd -S tcp:SQLSRVR\NAMEINST,59992 -E) work ...

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