A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
One of these might help:
Were you recently using two monitors or a monitor with a laptop and have now switched to one monitor or just the laptop, or has the field window been moved from the viewable area?
Select a cell within the range of your pivot table.
Press F10
Press CTRL+TAB
Press CTRL+SPACE
Press M
Press the Up Arrow key
Move your mouse around and left click to drop the window somewhere you can see it.
Are macros enabled in your workbook, or are you prompted to run macros when opening the workbook?
Try running this:
Sub Macro99()
ActiveWorkbook.ShowPivotTableFieldList = True
End Sub