When you are using HTMLParser.Net you may run into this error. The reason for this error is that the library depends on presence of following two configuration files.
This is the error message you will get from exception handler.The type initializer for 'Winista.Text.HtmlParser.Http.HttpProtocol' threw an exception.
Library expects these two files to be present in the folder from where your application is being executed. If you are using it in ASP.Net application then it will expect it to be in BIN folder of application. In community version of the library it is not possible to specify location of these files. But in PRO version of the library you can set the folder path where these configuration files are present and then library will grab the files from there instead of from execution folder.