Element 'NChartControl' is not a known element.
This can occur if there is a compilation error in the Web site, or the web.config file is missing.

And i cannot paste module chart or dragdrop it on aspx page or ascx because i use this version "dotnetvision2010Vol1VS2010.zip"
i try to install new version "dotnetvision2011Vol1VS2010.zip" it not work
and i come back to "dotnetvision2010Vol1VS2010.zip" it still not work

Hi Watit,

Please make sure you have the following dlls in the Bin folder of the ASP.NET application/website:

Nevron.System.dll
Nevron.GraphicsCore.dll
Nevron.GraphicsGL.dll
Nevron.UI.WebForm.Controls.dll
Nevron.Chart.dll
Nevron.Chart.WebForm.dll

This should fix the compilation issue.

Best Regards,
Nevron Support Team

yes,i'm sure
now i test on another pc , it not be my pc.