diff --git a/funcext/TSOffice/worksheet/xlsxWorkBook.tsf b/funcext/TSOffice/worksheet/xlsxWorkBook.tsf
index 0788cc4..889d4af 100644
--- a/funcext/TSOffice/worksheet/xlsxWorkBook.tsf
+++ b/funcext/TSOffice/worksheet/xlsxWorkBook.tsf
@@ -618,9 +618,17 @@ Type xlsxWorkBook = Class
 
 		//app.xml
 		app := GetXmlFileObj(class(TSXml).GetFileName('docProps_app'));
-		vector := app.FirstChildElement('Properties').FirstChildElement('TitlesOfParts').FirstChildElement('vt:vector');
+		prop := app.FirstChildElement('Properties');
+		vector := prop.FirstChildElement('TitlesOfParts').FirstChildElement('vt:vector');
 		vector.SetAttribute('size', sheetsCount_+1);
 		vector.InsertEndChild('element', 'vt:lpstr', destSheet);
+		vector := prop.FirstChildElement('HeadingPairs').FirstChildElement('vt:vector');
+		if ifObj(vector) then
+		begin
+			variant := vector.FirstChildElement('vt:variant').NextElement('vt:variant');
+			i4 := variant.FirstChildElement('vt:i4');
+			i4.SetValue(sheetsCount_ + 1);
+		end
 
 		//[Content_Types].xml
 		content_xml := GetXmlFileObj(class(TSXml).GetFileName('Content_Types'));