Insert > Headers and Footers grayed out, can't select

• Using LibO v5.2.2.2 Calc under Windoze 7, 64-bit PC w/GB of RAM.
• Workbook has three tabs, currently only two months and one tab is for a YTD summary.
• No tab will allow me to create either a header or footer.

Will gladly give any other info requested but don’t know what else to offer at this time.

Fortunately that menu item is rather useless anyway.
Go > ‘Format’ > ‘Page…’ to create Heders / Footers first. I suppose the menu item you talked of will no longer be grayed out subsequently. (Simply misleading.)