1. web.config를 열고 <configuration> 아래에 추가합니다.
<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<assemblyIdentity name="Newtonsoft.Json" publicKeyToken="30ad4fe6b2a6aeed" culture="neutral" />
<bindingRedirect oldVersion="0.0.0.0-11.0.0.0" newVersion="4.0.0.0" />
</dependentAssembly>
</assemblyBinding>
</runtime>