Web.config

<?xml version="1.0"?>
<configuration>
  <configSections>
    <sectionGroup name="dotNetOpenAuth" type="DotNetOpenAuth.Configuration.DotNetOpenAuthSection, DotNetOpenAuth.Core">
      <section name="messaging" type="DotNetOpenAuth.Configuration.MessagingElement, DotNetOpenAuth.Core" requirePermission="false" allowLocation="true"/>
      <section name="reporting" type="DotNetOpenAuth.Configuration.ReportingElement, DotNetOpenAuth.Core" requirePermission="false" allowLocation="true"/>
      <section name="oauth" type="DotNetOpenAuth.Configuration.OAuthElement, DotNetOpenAuth.OAuth" requirePermission="false" allowLocation="true"/>
      <section name="openid" type="DotNetOpenAuth.Configuration.OpenIdElement, DotNetOpenAuth.OpenId" requirePermission="false" allowLocation="true"/>
    </sectionGroup>
  </configSections>
  <system.webServer>
    <httpErrors errorMode="Custom" defaultResponseMode="Redirect">
      <remove statusCode="404" subStatusCode="-1"/>
      <error statusCode="404" prefixLanguageFilePath="" path="http://localhost:81/redi/a/" responseMode="Redirect"/>
    </httpErrors>
  </system.webServer>
  <!--
    For a description of web.config changes see http://go.microsoft.com/fwlink/?LinkId=235367.

    The following attributes can be set on the <httpRuntime> tag.
      <system.Web>
        <httpRuntime targetFramework="4.8" />
      </system.Web>
  -->
  <system.web>
    <compilation debug="true" targetFramework="4.8">
      <assemblies>
        <add assembly="System.Configuration, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"/>
      </assemblies>
    </compilation>
    <customErrors mode="Off">
      <error statusCode="404" redirect="~/Default.cshtml"/>
    </customErrors>
    <webServices>
      <protocols>
        <add name="HttpGet"/>
        <add name="HttpPost"/>
      </protocols>
    </webServices>
    <pages controlRenderingCompatibilityVersion="4.0"/>
  </system.web>
  <system.net>
    <defaultProxy enabled="true"/>
    <settings>
      <!-- This setting causes .NET to check certificate revocation lists (CRL) 
           before trusting HTTPS certificates.  But this setting tends to not 
           be allowed in shared hosting environments. -->
      <!--<servicePointManager checkCertificateRevocationList="true"/>-->
    </settings>
  </system.net>
  <runtime>
    <!-- This prevents the Windows Event Log from frequently logging that HMAC1 is being used (when the other party needs it). -->
    <legacyHMACWarning enabled="0"/>
    <!-- When targeting ASP.NET MVC 3, this assemblyBinding makes MVC 1 and 2 references relink
         to MVC 3 so libraries such as DotNetOpenAuth that compile against MVC 1 will work with it.
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
      </dependentAssembly>
    </assemblyBinding>
     -->
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="DotNetOpenAuth.AspNet" publicKeyToken="2780ccd10d57b246" culture="neutral"/>
        <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0"/>
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="DotNetOpenAuth.Core" publicKeyToken="2780ccd10d57b246" culture="neutral"/>
        <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0"/>
      </dependentAssembly>
    </assemblyBinding>
  </runtime>
  <dotNetOpenAuth>
    <messaging>
      <untrustedWebRequest>
        <whitelistHosts>
          <!-- Uncomment to enable communication with localhost (should generally not activate in production!) -->
          <!--<add name="localhost" />-->
        </whitelistHosts>
      </untrustedWebRequest>
    </messaging>
    <!-- Allow DotNetOpenAuth to publish usage statistics to library authors to improve the library. -->
    <reporting enabled="true"/>
    <!-- This is an optional configuration section where aspects of dotnetopenauth can be customized. -->
    <!-- For a complete set of configuration options see http://www.dotnetopenauth.net/developers/code-snippets/configuration-options/ -->
    <openid>
      <relyingParty>
        <security requireSsl="false">
          <!-- Uncomment the trustedProviders tag if your relying party should only accept positive assertions from a closed set of OpenID Providers. -->
          <!--<trustedProviders rejectAssertionsFromUntrustedProviders="true">
            <add endpoint="https://www.google.com/accounts/o8/ud" />
          </trustedProviders>-->
        </security>
        <behaviors>
          <!-- The following OPTIONAL behavior allows RPs to use SREG only, but be compatible
               with OPs that use Attribute Exchange (in various formats). -->
          <add type="DotNetOpenAuth.OpenId.RelyingParty.Behaviors.AXFetchAsSregTransform, DotNetOpenAuth.OpenId.RelyingParty"/>
        </behaviors>
      </relyingParty>
    </openid>
  </dotNetOpenAuth>
  <uri>
    <!-- The uri section is necessary to turn on .NET 3.5 support for IDN (international domain names),
         which is necessary for OpenID urls with unicode characters in the domain/host name.
         It is also required to put the Uri class into RFC 3986 escaping mode, which OpenID and OAuth require. -->
    <idn enabled="All"/>
    <iriParsing enabled="true"/>
  </uri>
  <system.data>
    <DbProviderFactories>
      <remove invariant="System.Data.SqlServerCe.4.0"/>
      <add invariant="System.Data.SqlServerCe.4.0" name="Microsoft® SQL Server® Compact 4.0" description=".NET Framework Data Provider for Microsoft SQL Server Compact" type="System.Data.SqlServerCe.SqlCeProviderFactory, System.Data.SqlServerCe, Version=4.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91"/>
    </DbProviderFactories>
  </system.data>
</configuration>