Does anyone have any idea why when I specify the actual Server Name in my DSN it'll allow me to create multiple connections to my SQL Server using a variety of logins. But, when I specify the Server I.P. address I can only create one connection with my DSN, if I try and create any more I get this error:

Connection Failed

SQL State: '0100o'

SQL Server Error: 14

[Microsoft][ODBC SQL Server Driver][TCP/IP Sockets]ConnectionOpnen (Invalid Instance()).

Thanks in advance.