EPiServer.Core.ContentNotFoundException: Content with id -1_-1 was not found

Hi

We're getting a reccuring error in our logs in the production environment. I have no ide where to start looking to get rid of this message. I can't see any issues in edit/admin or viewmode either. 

Does anybody have any ideas where to start looking?

Level

ERROR

Logger

EPiServer.Global

Message:

1.2.5 Unhandled exception in ASP.NET
EPiServer.Core.ContentNotFoundException: Content with id -1_-1 was not found
   at EPiServer.Core.Internal.DefaultContentLoader.Get[T](ContentReference contentLink, LoaderOptions loaderOptions)
   at EPiServer.Cms.Shell.UI.Rest.ContentQuery.GetChildrenQuery.GetChildren(ContentQueryParameters parameters, ContentReference parentId, LanguageSelector selector)
   at EPiServer.Cms.Shell.UI.Rest.ContentQuery.GetChildrenQuery.GetContent(ContentQueryParameters parameters)
   at EPiServer.Cms.Shell.UI.Rest.ContentQuery.ContentQueryBase.ExecuteQuery(IQueryParameters parameters)
   at EPiServer.Cms.Shell.UI.Rest.Internal.ContentStore.Get(ContentReference id, String query, ContentReference referenceId, ContentReference[] references, String[] typeIdentifiers, Nullable`1 allLanguages, IEnumerable`1 sortColumns, ItemRange range)
   at lambda_method(Closure , ControllerBase , Object[] )
   at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters)
   at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.b__39(IAsyncResult asyncResult, ActionInvocation innerInvokeState)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.b__3d()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<>c__DisplayClass46.b__3f()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<>c__DisplayClass46.b__3f()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<>c__DisplayClass46.b__3f()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass21.<>c__DisplayClass2b.b__1c()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass21.b__1e(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult)
   at EPiServer.Shell.Services.Rest.RestControllerBase.EndExecute(IAsyncResult asyncResult)
   at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
   at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)>>>>>>

Exception

EPiServer.Core.ContentNotFoundException: Content with id -1_-1 was not found
   at EPiServer.Core.Internal.DefaultContentLoader.Get[T](ContentReference contentLink, LoaderOptions loaderOptions)
   at EPiServer.Cms.Shell.UI.Rest.ContentQuery.GetChildrenQuery.GetChildren(ContentQueryParameters parameters, ContentReference parentId, LanguageSelector selector)
   at EPiServer.Cms.Shell.UI.Rest.ContentQuery.GetChildrenQuery.GetContent(ContentQueryParameters parameters)
   at EPiServer.Cms.Shell.UI.Rest.ContentQuery.ContentQueryBase.ExecuteQuery(IQueryParameters parameters)
   at EPiServer.Cms.Shell.UI.Rest.Internal.ContentStore.Get(ContentReference id, String query, ContentReference referenceId, ContentReference[] references, String[] typeIdentifiers, Nullable`1 allLanguages, IEnumerable`1 sortColumns, ItemRange range)
   at lambda_method(Closure , ControllerBase , Object[] )
   at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters)
   at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.b__39(IAsyncResult asyncResult, ActionInvocation innerInvokeState)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.b__3d()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<>c__DisplayClass46.b__3f()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<>c__DisplayClass46.>>