System.InvalidOperationException: Sequence contains no elements
at System.Linq.Enumerable.First[TSource](IEnumerable`1 source)
at _Default.XHtml..ctor(String path) in d:\Inetpub\domainid123580\public\Default.aspx.cs:line 1002
at _Default.GenerateDocument(String path, PItem DocItem) in d:\Inetpub\domainid123580\public\Default.aspx.cs:line 452
at _Default.GenerateDoc() in d:\Inetpub\domainid123580\public\Default.aspx.cs:line 109
at _Default.Page_Load(Object sender, EventArgs e) in d:\Inetpub\domainid123580\public\Default.aspx.cs:line 52