diff --git a/sheet.go b/sheet.go
index 351a5372..16b9a604 100644
--- a/sheet.go
+++ b/sheet.go
@@ -70,7 +70,7 @@ func (f *File) setWorkbook(name string, rid int) {
 	if err != nil {
 		fmt.Println(err)
 	}
-	f.saveFileList(`xl/workbook.xml`, replaceRelationshipsNameSpace(string(output)))
+	f.saveFileList(`xl/workbook.xml`, workBookCompatibility(replaceRelationshipsNameSpace(string(output))))
 }
 
 // Read and unmarshal workbook relationships of XLSX.
@@ -118,7 +118,7 @@ func (f *File) setAppXML() {
 // horrible hack to fix that after the XML marshalling is completed.
 func replaceRelationshipsNameSpace(workbookMarshal string) string {
 	oldXmlns := `<workbook xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main">`
-	newXmlns := `<workbook xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships">`
+	newXmlns := `<workbook xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="x15" xmlns:x15="http://schemas.microsoft.com/office/spreadsheetml/2010/11/main">`
 	return strings.Replace(workbookMarshal, oldXmlns, newXmlns, -1)
 }
 
@@ -200,5 +200,14 @@ func workBookCompatibility(workbookMarshal string) string {
 	workbookMarshal = strings.Replace(workbookMarshal, `></tabColor>`, ` />`, -1)
 	workbookMarshal = strings.Replace(workbookMarshal, `></pageSetUpPr>`, ` />`, -1)
 	workbookMarshal = strings.Replace(workbookMarshal, `></pane>`, ` />`, -1)
+	workbookMarshal = strings.Replace(workbookMarshal, `<extLst></extLst>`, ``, -1)
+	workbookMarshal = strings.Replace(workbookMarshal, `<fileRecoveryPr />`, ``, -1)
+	workbookMarshal = strings.Replace(workbookMarshal, `<workbookProtection />`, ``, -1)
+	workbookMarshal = strings.Replace(workbookMarshal, `<pivotCaches></pivotCaches>`, ``, -1)
+	workbookMarshal = strings.Replace(workbookMarshal, `<externalReferences></externalReferences>`, ``, -1)
+	workbookMarshal = strings.Replace(workbookMarshal, `<workbookProtection></workbookProtection>`, ``, -1)
+	workbookMarshal = strings.Replace(workbookMarshal, `<definedNames></definedNames>`, ``, -1)
+	workbookMarshal = strings.Replace(workbookMarshal, `<fileRecoveryPr></fileRecoveryPr>`, ``, -1)
+	workbookMarshal = strings.Replace(workbookMarshal, `<workbookPr />`, ``, -1)
 	return workbookMarshal
 }
diff --git a/xmlWorkbook.go b/xmlWorkbook.go
index b5c68797..c1969000 100644
--- a/xmlWorkbook.go
+++ b/xmlWorkbook.go
@@ -37,14 +37,17 @@ type xlsxWorkbook struct {
 	WorkbookProtection xlsxWorkbookProtection `xml:"workbookProtection"`
 	BookViews          xlsxBookViews          `xml:"bookViews"`
 	Sheets             xlsxSheets             `xml:"sheets"`
+	ExternalReferences xlsxExternalReferences `xml:"externalReferences"`
 	DefinedNames       xlsxDefinedNames       `xml:"definedNames"`
 	CalcPr             xlsxCalcPr             `xml:"calcPr"`
+	PivotCaches        xlsxPivotCaches        `xml:"pivotCaches"`
+	ExtLst             xlsxExtLst             `xml:"extLst"`
 	FileRecoveryPr     xlsxFileRecoveryPr     `xml:"fileRecoveryPr"`
 }
 
 // xlsxFileRecoveryPr maps sheet recovery information.
 type xlsxFileRecoveryPr struct {
-	RepairLoad int `xml:"repairLoad,attr"`
+	RepairLoad int `xml:"repairLoad,attr,omitempty"`
 }
 
 // xlsxWorkbookProtection directly maps the workbookProtection element from the
@@ -122,6 +125,43 @@ type xlsxSheet struct {
 	State   string `xml:"state,attr,omitempty"`
 }
 
+// xlsxExternalReferences directly maps the externalReferences element
+// of the external workbook references part.
+type xlsxExternalReferences struct {
+	ExternalReference []xlsxExternalReference `xml:"externalReference"`
+}
+
+// xlsxExternalReference directly maps the externalReference element
+// of the external workbook references part.
+type xlsxExternalReference struct {
+	RID string `xml:"http://schemas.openxmlformats.org/officeDocument/2006/relationships id,attr,omitempty"`
+}
+
+// xlsxPivotCaches element enumerates pivot cache definition parts
+// used by pivot tables and formulas in this workbook.
+type xlsxPivotCaches struct {
+	PivotCache []xlsxPivotCache `xml:"pivotCache"`
+}
+
+// xlsxPivotCache directly maps the pivotCache element.
+type xlsxPivotCache struct {
+	CacheID int    `xml:"cacheId,attr,omitempty"`
+	RID     string `xml:"http://schemas.openxmlformats.org/officeDocument/2006/relationships id,attr,omitempty"`
+}
+
+// extLst element provides a convention for extending spreadsheetML in
+// predefined locations. The locations shall be denoted with the extLst
+// element, and are called extension lists. Extension list locations
+// within the markup document are specified in the markup specification
+// and can be used to store extensions to the markup specification,
+// whether those are future version extensions of the markup specification
+// or are private extensions implemented independently from the markup
+// specification. Markup within an extension might not be understood by a
+// consumer.
+type xlsxExtLst struct {
+	Ext string `xml:",innerxml"`
+}
+
 // xlsxDefinedNames directly maps the definedNames element from the
 // namespace http://schemas.openxmlformats.org/spreadsheetml/2006/main
 // - currently I have not checked it for completeness - it does as
diff --git a/xmlWorksheet.go b/xmlWorksheet.go
index be7dcc2c..4752a158 100644
--- a/xmlWorksheet.go
+++ b/xmlWorksheet.go
@@ -26,6 +26,7 @@ type xlsxWorksheet struct {
 	LegacyDrawing xlsxLegacyDrawing `xml:"legacyDrawing"`
 	Picture       xlsxPicture       `xml:"picture"`
 	TableParts    xlsxTableParts    `xml:"tableParts"`
+	ExtLst        xlsxExtLst        `xml:"extLst"`
 }
 
 // xlsxDrawing change r:id to rid in the namespace.