Describes the cause and action for error messages.
Error Message(English)：
2016 missing track changes
Track changes in a Shared Workbook - Office Support
https://support.office.com/en-us/article/track-changes-in-a-shared-workbook-22aea671-cac7-4fa3-845d-・・・
Vanishing Excel Features and How to Handle Them | AccountingWEB
https://www.accountingweb.com/technology/excel/vanishing-excel-features-and-how-to-handle-them
How to track changes in Excel - Ablebits.com
https://www.ablebits.com/office-addins-blog/2017/08/09/track-changes-excel/
How to Enable and Use Track Changes in Excel - Trump Excel
https://trumpexcel.com/track-changes-in-excel/
Excel 2016: Track Changes and Comments - YouTube
https://www.youtube.com/watch?v=-9HmwO9u2aE
https://www.youtube.com/watch?v=-9HmwO9u2aE
How to Recover Excel file Unsaved or Lost - YouTube
https://www.youtube.com/watch?v=tCKEzgGcqFA
https://www.youtube.com/watch?v=tCKEzgGcqFA
How to Share Excel Workbooks and Track Changes Easily [2019]
https://spreadsheeto.com/share-workbooks/