Have you completed an upgrade recently?

What version are you running?

Can you try to go to http://yoursite.com/umbraco/umbraco.aspx. Just in case there is something to do with popup window.

Cheers

I guess this might be related to the code that gets the tree from the server-side. I had some similiar problems.
Make sure you run the correct version of System.Web.Extensions and AjaxControlToolkit (the ones that come with the installation)

I also had some troubles running Umbraco with .NET 3.5. I had to port (redirect) the version of System.Web.Extensions that are used by Umbraco to the onces provided by the 3.5 framework. Don't know if this will work for you, but you might give it a try...

In web.config

    <runtime>
      <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="3.5.0.0"/>
        </dependentAssembly>
        <dependentAssembly>
          <assemblyIdentity name="System.Web.Extensions.Design" publicKeyToken="31bf3856ad364e35"/>
          <bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="3.5.0.0"/>
        </dependentAssembly>
      </assemblyBinding>
    </runtime>

I'm running into this same issue and posted on this thread - http://our.umbraco.org/forum/using/ui-questions/1933-Backend-Menu-Broken-in-v4.  

My content doesn't show up, context menus do not display, and subfolders in the admin site (users, settings, developer, members).  My web.config has the above section specifiied for .NET 3.5 compatability and still nothing.

Any suggestions?

Thanks!

Thanks for the suggestions, I have now tried replacing the runtimeconfig section and also reapplied the permisions for the users but still no luck.

I am running version 4 and have not upgraded. It went went wrond when my ftp client uploaded a file and did not check to see if it wanted overwritting. I had miss clicked and then my web.config file had been overwritted and the site stopped working. I took another umbraco config file and up in the database connecion string and the user site started working but not the admin site.

I want to compare the file to a backed up version but not of our system admins who do this are around and I need to get it working today :(

Thanks for you help though

Andy

Hi all,

At the time of this issues there was an Umbraco update available and I ran that and it fixed it.

We've just updated some .net User Controls and the issue has returned?

Don't know how to fix it?

Any ideas?

Andrew

I'm running 
- Umbraco v 4.0.2.1 (Assembly version: 1.0.3441.17657)
- Have included web.config update to handle .net 3.5

Just to note, I believe this issue was that some umbraco dlls were overwritten by accident when updating dlls for User Controls.
Restored umbraco dlls froms a back up and all good now.

Cheers,

Andrew

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