The SqlDataSource component
uses standard ADO.NET objects and the installed on the machine data providers to establish a connection to the specified in the connection string database and to retrieve data.
The used data provider must be properly installed and registered on the machine. Also it must be considered with the target platform for the application (x86, AnyCPU). For more details check the Data provider is missing in the SqlDataSource wizard
Let us know if you have any further questions.
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