As far as I know, VB6 is the final version of classical VB, and there is no newer version to upgrade.
There is a VB in the .NET Framework, but it is incompatible with classical VB. If you change to the VB in the .NET Framework, I suggest you use ChartDirector for .NET instead.
If you are still using VB6 (since there is no newer version), you should still be using the VB6 IDE, and your project has added a reference to the ChartDirector component. In the VB6 IDE, you can open the Immediate Window (choose View/Immediate Window), and you can manually enter the following code to see what is the result:
Set cd = CreateObject("ChartDirector.API")
The cd.getVersion line will print out the ChartDirector version you are using. The cd.getBootLog line will display why the license key cannot be loaded.