OPC client development component for .NET (DotNet) OPC DA client applications. The OPCDA.NET component provides .Net classes and methods take advantage of the .NET features and make OPC DA Server access real simple and highly efficient. The OPC DA functions are provided as methods with easy to use .NET friendly interface. Visual Studio .Net wizards create new OPC DA client applications or add OPC DA access functionality to existing applications. Extensive help documentation integrates into Visual Studio's help system and offers the programmer context sensitive help. Helper classes simplify the OPC DA interface for browsing and item read/write access. The hand coded wrapper layer for .Net COM access offers top performance while making all the type conversion for convenient use. OPCDA.NET is the first component to support 64-bit operation.