Interface not valid for Implements

Not all interfaces can be implemented in Visual Basic. This error has the following cause and solution:

• The interface contains some element that can't be supported by Visual Basic. For example, Visual Basic has no equivalent to the unsigned long integer type, Visual Basic can't designate a procedure parameter as "out-only." Although Visual Basic supports the use of the underscore character (_) in Visual Basic identifiers, it can't implement an interface that uses underscore characters in the names of its members.

  You can't implement the interface in Visual Basic.

For additional information, select the item in question and press F1 (in Windows) or HELP (on the Macintosh).

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