Ошибка при записи в blob

	var ID = '{251FB9AC-C17E-4DF7-A0CB-D591FDB97462}';
 
	var ContactDataset = Services.GetNewItemByUSI('ds_Contact');
	EnableDatasetFilters(ContactDataset, false);    
    ApplyDatasetFilter(ContactDataset, 'ID', ID, true);
    ContactDataset.Open();
 
    var DescriptionDataset = Services.GetNewItemByUSI('ds_Description');
	ApplyDatasetFilter(ContactDataset, 'ID', ID, true);
 
	var SubjectSelectQuery = ContactDataset.SelectQuery;
	var DetailSelectQuery = DescriptionDataset.SelectQuery;
	var FromTable = SubjectSelectQuery.Items(0).FromTable;
	DetailSelectQuery.Items(0).FromTable = FromTable;
	DescriptionDataset.Open(); 
 
    var FieldName = ContactDataset.DataFields.ItemsByName('Name');
    var FieldDescription = DescriptionDataset.DataFields.ItemsByName('Description');
 
 
    var Stream = new ActiveXObject('ADODB.Stream');
	Stream.CharSet = 'windows-1251';
    Stream.Mode = 3;
    Stream.Type = 2;
	Stream.Open();
    Stream.Position = 0;
    Stream.WriteText(FieldName.Value); 
 
    DescriptionDataset.Edit();
    FieldDescription.SetValAsBlob(Stream);
    Stream.Close();
    DescriptionDataset.Post();
 
    DescriptionDataset.Close();
    ContactDataset.Close();