How to C#: HTML5 Viewer

C# FAQs for XDoc.HTML5 Viewer

Frequently Asked Questions for Using XDoc.HTML5 Viewer in C# Programming

On this page, you will see frequently asked questions from customers for using our HTML5 Document Viewer Control in their C# applications. If you have additional questions or requests, please send email to

C# FAQ: 500.19 Error Occur

If you configure IIS to run and 500.19 error occurs, then it may be caused by:

Not registered .NET Framework to IIS. (One of reasons: install a .NET Framework before the installation of IIS.)

The site configured in IIS has no permission to operate. (Modify permission)

Here are some solutions:

cd to C:\Windows\Microsoft.NET\Framework64\v2.0.50727, Command to re-register .NET Framework to the iis:aspnet_regiis-i.

Right-click the correspond site-> Edit Permissions -> Security -> Group or user names -> Edit -> Add -> Add Everyone usersgiven Full Control permissions.

C# FAQ: Document Uploading Failed

If document uploading is not successful in your C#.NET web project, please pay attention to the following:

Make sure the Default page is the Default. aspx. If not sure, in the address bar, please add /Default.aspx.

Don't add SVGWebViewer dll to the project.

C# FAQ: Debug Error When Adding DLL

In your C# ASP.NET project, you get this error when testing web viewer control: "Could not load file or assembly 'RasterEdge.Imaging.Annotation' or one of its dependencies. An attempt was made to load a program with an incorrect format."

This is because some versions of Visual Studio use a 32-bit web server internally. You can firstly debug with x86 webviewer dlls in Visual Studio mimic IIS environment. Once done debugging with x86 dlls, replace the x86 with x64 version of dlls to run in real IIS on the server.

For example, if your computer is x64, you can set "Enable 32-Bit Applications" to true or false in corresponding Application pool (True: x86; False: x64).