Hello.

I am currently having a problem with linq querying on umbraco 4.7.1.

I have a class for data context which looks like this:

public partial class CustomerServiceDataContext : UmbracoDataContext {
...
public Tree<Request> Requests
        {
            get
            {
                return this.LoadTree<Request>();
            }
        }
....
}

I have a razor script that renders list of requests with paging.

IEnumerable<CustomerServiceNamespace.Request> requests = from t in ctx.Requests select t;
*some conditional Where()s*....
var numberOfItems = requests.Count( );

The problem is Count().

I randomly get the following error:

System.InvalidCastException: Unable to cast type of current object to type of value
   at System.Convert.ChangeType(Object value, Type conversionType, IFormatProvider provider)
   at umbraco.Linq.Core.Node.NodeDataProvider.LoadFromXml[T](XElement xml, T node)
   at umbraco.Linq.Core.Node.NodeTree`1.GetEnumerator()
   at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
   at System.Linq.Enumerable.Count[TSource](IEnumerable`1 source, Func`2 predicate)
   at ASP._Page_macroScripts_RenderRequestList_cshtml.Execute() c:\inetpub\Umbraco\macroScripts\RenderRequestList.cshtml:column 66

(Sorry, battling with russian translation for exceptions)

I also get the same error all the time if I step into the script with debugger. And randomly get same error for some other trees in context. (ex: ctx.Regions.Count()) Couldn't find this cause or simmilarities.

Any help would be appreciated.