Currently I've problem using custom config section, I've tested this config section with unit testing and it works perfectly, but when I used it in a WCF Service hosted in IIS 8 it produced an error:
Config Error: Only one <configSections> element allowed. It must be the first child element of the root <configuration> elementMore Information: This error occurs when there is a problem reading the configuration file for the Web server or Web application. In some cases, the event logs may contain more information about what caused this error. If you see the text "There is a duplicate 'system.web.extensions/scripting/scriptResourceHandler' section defined", this error is because you are running a .NET Framework 3.5-based application in .NET Framework 4. If you are running WebMatrix, to resolve this problem, go to the Settings node to set the .NET Framework version to ".NET 2". You can also remove the extra sections from the web.config file. View more information »
How to solve this issue? Thanks in advance.