Hi,
I have done an upgrade on my local machine of umbraco cms
to the latest version and everything works fine apart from the media section.
I can add new files and the work fine but all the already existing nodes give the following error:

I am using the legacyschema setting to true.

<UseLegacyXmlSchema>true</UseLegacyXmlSchema>

Would really appreciate if anyone could give any hints on how to fix this.
I would hope it is not permissions as I have set the app pool to run as an administrator
I have though of datatypes issues but how could I debug/fix this?

The best hint so far is that I can add new images and modify them but can't open existing files

3005 

   An unhandled exception has occurred. 

   05/04/2011 15:48:31 

   05/04/2011 14:48:31 

   582d29c7106a42cc9c8bada627f87c70 

   4 

   1 

   0 

   /LM/W3SVC/2/ROOT-13-129464885053410625 

   Full 

   / 

   D:\Projects\Umbraco47\Website\ 

   MYPC 

   2180 

   w3wp.exe 

   NT AUTHORITY\NETWORK SERVICE 

   NullReferenceException 

   Object reference not set to an instance of an object. at umbraco.controls.ContentControl.addControlNew(Property p, TabPage tp, String Caption) at umbraco.controls.ContentControl.CreateChildControls() at System.Web.UI.Control.EnsureChildControls() at umbraco.controls.ContentControl.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.AddedControl(Control control, Int32 index) at System.Web.UI.ControlCollection.Add(Control child) at umbraco.cms.presentation.editMedia.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)  

   http://localhost/umbraco/editMedia.aspx?id=3156 ;

   /umbraco/editMedia.aspx 

   ::1 

   False 

   Administrator 

   18 

   Administrator 

   False 

   at umbraco.controls.ContentControl.addControlNew(Property p, TabPage tp, String Caption) at umbraco.controls.ContentControl.CreateChildControls() at System.Web.UI.Control.EnsureChildControls() at umbraco.controls.ContentControl.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.AddedControl(Control control, Int32 index) at System.Web.UI.ControlCollection.Add(Control child) at umbraco.cms.presentation.editMedia.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)