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Conversion operators cannot convert from a base type

Visual Studio 2008

A conversion operator is declared with a parameter type from which the return type derives.

At compile time, Visual Basic considers a predefined conversion to exist from any reference type to any type in its inheritance hierarchy, that is, any type from which it derives or which derives from it. Such a conversion might fail at run time, but the compiler cannot predict run-time results, so it allows any such conversion to compile.

Because the compiler considers this conversion to be already defined, it does not allow you to redefine it.

Error ID: BC33030

To correct this error

  • Remove this operator definition entirely. It is already predefined.