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Need a viewer UI in


I need viewer UI in
I Tried many of your samples those got examples for convert files.
I need to show the converted file in your viewer with the viewer operations.

So please provide ASP.Net viewer UI .

Thanks & Regards,



You can download our open source web UI samples that are developed in ASP.NET from the following links.


I download and Tried your web samples.
after restored nuget packages I got this following error when I build.

Error The CodeDom provider type “Microsoft.CodeDom.Providers.DotNetCompilerPlatform.CSharpCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35” could not be located. (E:\New folder (6)\github\GroupDocs.Viewer-for-.NET-WebForms-master\src\web.config line 147) E:\New folder (6)\github\GroupDocs.Viewer-for-.NET-WebForms-master\src\Global.asax 1

Error Could not load type ‘GroupDocs.Viewer.WebForms.Global’. E:\New folder (6)\github\GroupDocs.Viewer-for-.NET-WebForms-master\src\Global.asax 1

Please Help to resolve




We are unable to reproduce this issue and it seems that the issue is only happening at your end. I would suggest you try the following resolutions one by one to fix the issue:

  • Check if Microsoft.CodeDom.Providers.DotNetCompilerPlatform is missing in the references. If so, add it using the NuGet Package Manager.
  • It is possible that there is the difference of the version of Microsoft.CodeDom.Providers.DotNetCompilerPlatform.dll and the version attribute that is written in <system.codedom> part in web.config (see this). So you may try updating the version attribute in the web.config. You may also try to reinstall the package (uninstall and then install again).
  • Uninstall the Microsoft.CodeDom.Providers.DotNetCompilerPlatform package and remove <system.codedom> part from the web.config.

Make sure that you do clean and rebuild the solution after making the changes. For more assistance, you may also consult this article. Hope it helps.