I'm using Orchard 1.6 and would like to move the using directives from the Razor views to the Views folder web.config. This is a custom module. The syntax is described here - http://stackoverflow.com/questions/3239006/how-to-import-a-namespace-in-razor-view-page#6723046 - but I can't get it to work (the views can't find the classes).

Are you doing this in the web.config of your module, or of the Orchard.Web project?

There is a separate web.config in the Views folder of my module, which looks like the perfect place to do this.

Are you saying that's where you tried it? Why not try Orchard.Web\web.config and see if it works?

Because I want a specific namespace to be available in a single module views.

Right, makes sense, my mistake.

I've done what you're asking by editing the web.config of my module in two places. In my case I was adding the System.Transactions namespace to be available in my module's Razor views:

<configuration>
<system.web.webPages.razor>
    <host factoryType="System.Web.Mvc.MvcWebRazorHostFactory, System.Web.Mvc, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
    <pages pageBaseType="Orchard.Mvc.ViewEngines.Razor.WebViewPage">
      <namespaces>
        <add namespace="System.Web.Mvc" />
        <add namespace="System.Web.Mvc.Ajax" />
        <add namespace="System.Web.Mvc.Html" />
        <add namespace="System.Web.Routing" />
        <add namespace="System.Linq" />
        <add namespace="System.Collections.Generic" />
        <add namespace="Orchard.Mvc.Html" />
        <add namespace="System.Transactions" />
      </namespaces>
    </pages>
  </system.web.webPages.razor>
</configuration>

<configuration>
  <system.web>
    <compilation targetFramework="4.0">
      <assemblies>
        <add assembly="System.Web.Abstractions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
        <add assembly="System.Web.Helpers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
        <add assembly="System.Web.Routing, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
        <add assembly="System.Data.Linq, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089" />
        <add assembly="System.Web.Mvc, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
        <add assembly="System.Web.WebPages, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
        <add assembly="System.Data, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" />
       <add assembly="System.Transactions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" />
      </assemblies>
    </compilation>
  </system.web>
</configuration>

Great, works for me.

Thanks Your Highness ;)