converting to xlsx error
 

I get an error on my cable records when I open the file in the converted
..xlsx format €¦ it happens every time I close the file and reopen. I am
worried that my saves are not saving data properly.
the error she is getting is
repair to 'document.xlsx'
excel was able to open the file by repairing or removing the unreadable
content

removed records: formula from /xl/worksheets/shett1.xml
part
Removed Records: Formula from /xl/calcahin.xml part
(calculation Properties)

can someone tell what this is?