Driver={SQL Native Client};Server=myServerAddress;Database=myDataBase;Uid=myUsername;Pwd=myPassword;

Are you using SQL Server 2005 Express? Don't miss the server name syntax Servername\SQLEXPRESS where you substitute Servername with the name of the computer where the SQL Server 2005 Express installation resides.

Trusted Connection

Driver={SQL Native Client};Server=myServerAddress;Database=myDataBase;Trusted_Connection=yes;

Equivalent key-value pair: "Integrated Security=SSPI" equals "Trusted_Connection=yes"

Connecting to an SQL Server instance

The syntax of specifying the server instance in the value of the server key is the same for all connection strings for SQL Server.

Driver={SQL Native Client};Server=myServerName\theInstanceName;Database=myDataBase;Trusted_Connection=yes;

Using a non-standard port

If your SQL Server listens on a non-default port you can specify that using the servername,xxxx syntax (note the comma, it's not a colon).

Driver={SQL Native Client};Server=myServerName,myPortNumber;Database=myDataBase;Uid=myUsername;Pwd=myPassword;

The default SQL Server port is 1433 and there is no need to specify that in the connection string.

Prompt for username and password

This one is a bit tricky. First you need to set the connection object's Prompt property to adPromptAlways. Then use the connection string to connect to the database.

oConn.Properties("Prompt") = adPromptAlways

oConn.Open "Driver={SQL Native Client};Server=myServerAddress;Database=myDataBase;"

Enable MARS

Driver={SQL Native Client};Server=myServerAddress;Database=myDataBase;Trusted_Connection=yes;MARS_Connection=yes;

Encrypt data sent over network

Driver={SQL Native Client};Server=myServerAddress;Database=myDataBase;Trusted_Connection=yes;Encrypt=yes;

Attach a database file on connect to a local SQL Server Express instance

Driver={SQL Native Client};Server=.\SQLExpress;AttachDbFilename=c:\mydbfile.mdf;Database=dbname;Trusted_Connection=Yes;

Why is the Database parameter needed? If the named database have already been attached, SQL Server does not reattach it. It uses the attached database as the default for the connection.

Attach a database file, located in the data directory, on connect to a local SQL Server Express instance

Driver={SQL Native Client};Server=.\SQLExpress;AttachDbFilename=|DataDirectory|mydbfile.mdf;Database=dbname;Trusted_Connection=Yes;

Why is the Database parameter needed? If the named database have already been attached, SQL Server does not reattach it. It uses the attached database as the default for the connection.

Database mirroring

If you connect with ADO.NET or the SQL Native Client to a database that is being mirrored, your application can take advantage of the drivers ability to automatically redirect connections when a database mirroring failover occurs. You must specify the initial principal server and database in the connection string and the failover partner server.

Driver={SQL Server Native Client 10.0};Server=myServerAddress;Failover_Partner=myMirrorServerAddress;Database=myDataBase;Trusted_Connection=yes;

There is ofcourse many other ways to write the connection string using database mirroring, this is just one example pointing out the failover functionality. You can combine this with the other connection strings options available.

Please note if you are using TCP/IP (using the network library parameter) and database mirroring, including port number in the address (formed as servername,portnumber) for both the main server and the failover partner can solve some reported issues.

SQL Server 2000

Standard security

Driver={SQL Native Client};Server=myServerAddress;Database=myDataBase;Uid=myUsername;Pwd=myPassword;

When to use SQL Native Client?

Trusted Connection

Driver={SQL Native Client};Server=myServerAddress;Database=myDataBase;Trusted_Connection=yes;

Equivalent key-value pair: "Integrated Security=SSPI" equals "Trusted_Connection=yes"

Connecting to an SQL Server instance

The syntax of specifying the server instance in the value of the server key is the same for all connection strings for SQL Server.

Driver={SQL Native Client};Server=myServerName\theInstanceName;Database=myDataBase;Trusted_Connection=yes;

Using a non-standard port

If your SQL Server listens on a non-default port you can specify that using the servername,xxxx syntax (note the comma, it's not a colon).

Driver={SQL Native Client};Server=myServerName,myPortNumber;Database=myDataBase;Uid=myUsername;Pwd=myPassword;

The default SQL Server port is 1433 and there is no need to specify that in the connection string.

Prompt for username and password

This one is a bit tricky. First you need to set the connection object's Prompt property to adPromptAlways. Then use the connection string to connect to the database.

oConn.Properties("Prompt") = adPromptAlways

oConn.Open "Driver={SQL Native Client};Server=myServerAddress;Database=myDataBase;"

Encrypt data sent over network

Driver={SQL Native Client};Server=myServerAddress;Database=myDataBase;Trusted_Connection=yes;Encrypt=yes;

SQL Server 7.0

Standard security

Driver={SQL Native Client};Server=myServerAddress;Database=myDataBase;Uid=myUsername;Pwd=myPassword;

When to use SQL Native Client?

Trusted Connection

Driver={SQL Native Client};Server=myServerAddress;Database=myDataBase;Trusted_Connection=yes;

Equivalent key-value pair: "Integrated Security=SSPI" equals "Trusted_Connection=yes"

Connecting to an SQL Server instance

The syntax of specifying the server instance in the value of the server key is the same for all connection strings for SQL Server.

Driver={SQL Native Client};Server=myServerName\theInstanceName;Database=myDataBase;Trusted_Connection=yes;

Using a non-standard port

If your SQL Server listens on a non-default port you can specify that using the servername,xxxx syntax (note the comma, it's not a colon).

Driver={SQL Native Client};Server=myServerName,myPortNumber;Database=myDataBase;Uid=myUsername;Pwd=myPassword;

The default SQL Server port is 1433 and there is no need to specify that in the connection string.

Prompt for username and password

This one is a bit tricky. First you need to set the connection object's Prompt property to adPromptAlways. Then use the connection string to connect to the database.

oConn.Properties("Prompt") = adPromptAlways

oConn.Open "Driver={SQL Native Client};Server=myServerAddress;Database=myDataBase;"

Encrypt data sent over network

Driver={SQL Native Client};Server=myServerAddress;Database=myDataBase;Trusted_Connection=yes;Encrypt=yes;