You don't need to remove the charts! Before I upgraded, I opened the VS project. Under "References" you see ChartFX.WinForms, ChartFX.WinForms.Base and ChartFX.WinForms.Adornments. If you click on one of them, you can set "Specific version" in the Properties page to "false". I did this for all of them. Then I closed VS, installed the new ChartFX. No error after opening the project! :-)