Hi Fernando,

There could be a problem with the result's STRING type.

So may be instead of

DECLARE STRING FunctionToExecute IN vb6dll STRING pStringParameter

program your VB interface to be called as

DECLARE INTEGER FunctionToExecute IN vb6dll;
	STRING pStringParameter, STRING @pOutputParameter

So the function may return Integer value indicating success (1) or failure (0). And the result is retuned with the second parameter.
This is how VB code might look:

Function FunctionToExecute(ByRef string1, ByRef string2) As Integer
	Dim result As Integer
...
	string2=... 'assign something to this string
	Return result
End Function