Describes the cause and action for error messages.
Error Message(English)：
why does excel not sum correctly
https://www.youtube.com/watch?v=cAoCB1HwPXU
How to Fix Excel Numbers That Don't Add Up - YouTube
https://www.youtube.com/watch?v=h8543MwnnTs
https://www.youtube.com/watch?v=h8543MwnnTs
5 Reasons Why your Excel Formula is Not Calculating - YouTube
https://www.youtube.com/watch?v=AvR1EtjToLk
https://www.youtube.com/watch?v=AvR1EtjToLk
Excel Tip of the Week #53 - Causes of formulas not calculating - Blogs ...
https://ion.icaew.com/itcounts/b/weblog/posts/exceltipoftheweek53causesofformulasnotcalculating
Excel cells do not add up correctly - Darn Office
https://darnoffice.com/excel-cells-do-not-add-up-correctly/
worksheet function - Excel isn't calculating the SUM of cells ...
https://superuser.com/questions/309181/excel-isnt-calculating-the-sum-of-cells
microsoft excel - Sum function is not working ...
https://superuser.com/questions/1225291/sum-function-is-not-working-properly