ADODB Connection string from (Word) VBA - "Multi-step OLE DB operation generated errors..."

Developing a Word (2010) Add-in that communicates with a SQL Server (2008) database.  This has worked successfully for weeks using an internal server name, and this connection string:

Set objConnection = New ADODB.Connection
objConnection.ConnectionString = "Provider=SQLOLEDB;Data Source=SERVERNAME;Initial Catalog=QualitativeDB;Integrated Security=SSPI"
objConnection.Open

Trying now to transition that to be a public facing address.  With help from www.connectionstrings.com, I'm trying this string.  

Set objConnection = New ADODB.Connection
objConnection.ConnectionString = "Provider=SQLOLEDB;Data Source=00.000.000.00,1433;Network Library=DBMSSOCN=TCP/IP;Initial Catalog=QualitativeDB;Integrated Security=SSPI"
objConnection.Open

I know I'm close because I get the "Multi-step..." SQL error message above, rather than just timing out.  I've tried it with and without the =TCP/IP, but with seems to get me closer.

Others who have asked about this error appear to be attempting some illegal SQL operation, but I'm hitting the error on objConnection.open.

Any idea how to tweak my connection string to work?  Thanks.