Hi there, I am using Umbraco 5 and I have started seeing the following error when trying to view my root content node "Home". I have recently added new properties to this node but they are all correct, theres no duplicate naming and Im not using any custom Property Editors. Can somebody please get back to me asap as this work has to be completed asap!

The error appears

'Umbraco.Cms.Web.PropertyEditors.ListPicker.ListPickerEditorModel' does not contain a definition for 'AvailableTemplates'

[RuntimeBinderException: 'Umbraco.Cms.Web.PropertyEditors.ListPicker.ListPickerEditorModel' does not contain a definition for 'AvailableTemplates']
   CallSite.Target(Closure , CallSite , Object ) +216
   Umbraco.Cms.Web.Editors.ContentEditorController.OnEditing(ContentEditorModel model, EntitySnapshot`1 entity) +2186
   Umbraco.Cms.Web.Editors.AbstractRevisionalContentEditorController`1.Edit(Nullable`1 id) +1260
   lambda_method(Closure , ControllerBase , Object[] ) +218
   System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) +264
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +39
   System.Web.Mvc.<>c__DisplayClass15.<InvokeActionMethodWithFilters>b__12() +129
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +826266
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +826266
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +826266
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +826266
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodWithFilters(ControllerContext controllerContext, IList`1 filters, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +314
   System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +825488
   Umbraco.Cms.Web.Mvc.ActionInvokers.ControllerExtenderActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +361
   System.Web.Mvc.Controller.ExecuteCore() +159
   System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +335
   System.Web.Mvc.<>c__DisplayClassb.<BeginProcessRequest>b__5() +62
   System.Web.Mvc.Async.<>c__DisplayClass1.<MakeVoidDelegate>b__0() +20
   System.Web.Mvc.<>c__DisplayClasse.<EndProcessRequest>b__d() +54
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +469
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +375