Excel group outline not showing

Describes the cause and action for error messages.

Error Message(English)：
group outline not showing

Resolution

Excel: Group rows automatically or manually, collapse and expand rows
https://www.ablebits.com/office-addins-blog/2017/12/28/excel-group-rows/

How to group rows in Excel
https://www.ablebits.com/office-addins-blog/2017/12/28/excel-group-rows/#group-rows-in-excel

How to collapse rows in Excel
https://www.ablebits.com/office-addins-blog/2017/12/28/excel-group-rows/#collapse-rows-in-excel

Excel grouping tips
https://www.ablebits.com/office-addins-blog/2017/12/28/excel-group-rows/#row-grouping-tips

How to show or hide outline symbols in Excel? - ExtendOffice
https://www.extendoffice.com/documents/excel/1180-excel-show-or-hide-outline-symbols.html

Excel Problem: Group and Ungroup not working in Excel - YouTube
https://www.youtube.com/watch?v=zYybjWrZZHQ

https://www.youtube.com/watch?v=zYybjWrZZHQ

Hiding Outline Symbols (Microsoft Excel) - Excel Ribbon Tips - Tips.Net
https://excelribbon.tips.net/T009269_Hiding_Outline_Symbols.html

Grouping outline symbols tab is not visible/hardly visible - Mr. Excel
https://www.mrexcel.com/forum/excel-questions/1020377-grouping-outline-symbols-tab-not-visible-hardl・・・