SQL Server and [DBNETLIB][ConnectionOpen (Connect()).]SQL Server does not exist or access denied.

In preparing for class, I was testing out some simple connection exercises from Excel.[OT: I was pleasantly surprised to note that you can access SQL Server 2005 (using Excel 2007) without setting up an ODBC connection string.] In the process, I could not connect to the SQL server instance on my local machine. I discovered that numerous others continue to face this problem as a google search on the error string will reveal. Having experienced this TYPE of situation since this past summer, I tried one of my tricks: Append the port number (even if it is the default). IT WORKS!

Environment: SQLServer 2005 and Excel 2007
Solution: Add the port number to your server name (serverName,nnnn)