A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
If it works in Safe mode but not in normal use, I would suspect an add-in or a program loaded at startup has disabled it.
In normal mode, Alt+F11 to the VB editor, Ctrl+G to the immediate pane and type
?Application.CommandBars("PivotTable Field List").Enabled
and hit Enter if it says False, type (or paste) the following line:
Application.CommandBars("PivotTable Field List").Enabled=True
and hit Enter.
Does it now behave correctly?
If so, disable add-ins (via Office Button > Add-Ins) and remove all workbooks from your XLSTART folders (which can be found by typing the following in the VB editor immediate window:)
?Application.Path & "\XLSTART"
?Application.StartupPath
?Application.AltStartupPath
Restart Excel and check it still behaves correctly.
You could then add back your add-ins and startup programs until you find the culprit.