diff --git a/funcext/TSOffice/worksheet/xlsxWorkBook.tsf b/funcext/TSOffice/worksheet/xlsxWorkBook.tsf
index 333145c..87f9570 100644
--- a/funcext/TSOffice/worksheet/xlsxWorkBook.tsf
+++ b/funcext/TSOffice/worksheet/xlsxWorkBook.tsf
@@ -336,7 +336,7 @@ Type xlsxWorkBook = Class
 		begin
 			if LowerCase(lpstr.GetText()) = LowerCase(sourceSheet) then
 			begin
-				if ifnil(pstr) then vector.InsertFirstChild('element', 'vt:lpstr');
+				if ifnil(pstr) then lpstr := vector.InsertFirstChild('element', 'vt:lpstr');
 				else lpstr := vector.InsertAfterChild(pstr, 'element', 'vt:lpstr');
 				lpstr.SetValue(destSheet);
 				break;