If every sheet tab is missing in Excel for Windows, maximize the workbook window, then check File → Options → Advanced → Display options for this workbook → Show sheet tabs. If you can still see some tabs, scroll along the tab strip before using Unhide on a visible tab.
01Restore the whole tab strip
Section linkMake sure you are looking at the intended workbook. Double-click the title bar to maximize its window. If windows overlap and the bottom still is not visible, use View → Arrange All → Tiled. Then check Show sheet tabs under the display options for the affected workbook. Test that workbook again after closing the options dialog.
02Make room for more sheet names
Section linkIf the horizontal scroll bar leaves almost no room for tabs, hover over the boundary between the tab area and the scroll bar until a double-headed arrow appears. Drag the boundary to the right. Use the small navigation buttons to the left of the sheet tabs to scroll through the names before assuming a sheet is hidden.
03Unhide a missing worksheet
Section linkRight-click any visible sheet tab and select Unhide. Select the sheet you need and confirm. A hidden worksheet can still supply values to formulas on other sheets. If the sheet is absent from the dialog, check that you opened the intended copy of the file. A worksheet marked VeryHidden through VBA does not appear in this dialog; ask the workbook owner about it before making changes.