Describes the cause and action for error messages.
Error Message(English)：
cancel protect workbook
Add or remove protection in your document, workbook, or presentation ...
https://support.office.com/en-us/article/add-or-remove-protection-in-your-document-workbook-or-prese・・・
Remove "Protect Workbook" Password in Excel | Hindi - YouTube
https://www.youtube.com/watch?v=BfbhQxrAB58
https://www.youtube.com/watch?v=BfbhQxrAB58
Removing Protection from a Protected Workbook (Microsoft Excel)
https://excelribbon.tips.net/T000073_Removing_Protection_from_a_Protected_Workbook.html
How to protect worksheets and unprotect Excel sheet without password
https://www.ablebits.com/office-addins-blog/2016/02/10/protect-unprotect-excel-sheet-password/
Excel worksheet protection ...
https://www.ablebits.com/office-addins-blog/2016/02/10/protect-unprotect-excel-sheet-password/#excel・・・
How to unlock Excel ...
https://www.ablebits.com/office-addins-blog/2016/02/10/protect-unprotect-excel-sheet-password/#unloc・・・
How to protect a workbook ...
https://www.ablebits.com/office-addins-blog/2016/02/10/protect-unprotect-excel-sheet-password/#prote・・・
Unprotect an Excel spreadsheet if you have lost your password
http://www.excelsupersite.com/how-to-unprotect-an-excel-spreadsheet-if-you-have-lost-your-password/