[Microsoft][ODBC SQL Server Driver][DBNETLIB]ConnectionOpen (Connect()). [ODBC SQL Server Driver][DBNETLIB]Specified SQL server not found
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Microsoft SQL Server Login
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Connection failed:
SQLState: '01000'
SQL Server Error: 11004
[Microsoft][ODBC SQL Server Driver][DBNETLIB]ConnectionOpen (Connect()).
Connection failed:
SQLState: '08001'
SQL Server Error: 6
[Microsoft][ODBC SQL Server Driver][DBNETLIB]Specified SQL server not found.
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OK
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I'm sure the above error message seems very familiar to you when trying to connect using a remote machine with SQL Server Management Studio or even it throws similar error when trying to create a DSN. First thing to check is SQL Server Configuration Manager to see whether TCP/IP is enabled under both (Network configuration for the named instance AND Sql Native Client Configuration).
For me (within the newsgroups) I get to see on the named instances, also you should check under Surface Area Configuration and ensure Remote Connections is enabled, as this is disabled by default. Further checkout is to see whether SQLBrowser service is started or not. It's disabled by default. It's required to enumerate the named instance names on a server. So if it's disabled, the named instance is not discoverable and cannot be connected remotely. Overall you should refer to KBA328306 for other reasons that might contribute for this error.