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I went through attached demo project and I can confirm that this is a type of corruption that is usually seen the MS Excel.
Here are the work around we can try in such cases:
1) If your Excel spreadsheet contains valuable data you can Make the Excel File ‘Read-only’:
2) You can also Install Visual Basic Component
3) You can get help using the third party software solely created for Data recovery of corrupted/ partially corrupted Excel files. While going through more such queries, I stumbled on this which is closely related yours and the solution works.
Commonly it is seen “We found a problem with some content in FileName.xlsx” appears to the users due to System file corruption and this affect the office files. So try repairing it
You can also try to recover the data from the Excel file by making it read-only
· Open Excel workbook in ‘read-only’ mode > try copying its entire contents.
· Now create a new workbook > paste the entire contents from the corrupted file to the new file.
FOR MOR FIXES PLEASE CHECK THIS POST: We Found A Problem With Some Content In Excel
You can follow the steps mentioned in the below article for repairing your corrupted excel file: