I installed Umbraco on a website a couple months ago.  Everything was working great.  I recently returned and logged in to Umbraco's admin interface to discover my Admin context menu and main body are empty.  The website still works, but I can't access content or any of the other additional functions.

I restarted the application instance and stopped/started the IIS instance. I verified that permission are still correct (I'm on a shared environment) and the section icons in the admin UI are there and appear to behave correctly.  I checked my AJAX reference, it appears to be correct (I think):

  <runtime>
    <!-- Old asp.net ajax assembly bindings -->
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Extensions" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="4.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Extensions.Design" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="4.0.0.0" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>

It's Umbraco 4.5.2 on .Net 4.0.

Any suggestions?

Respectfully,

Ray K. Ragan