(EXCEL 2010) Excel found unreadable content in 'xxx'.xlsx. Do you want to recover the contents of the workbook? If you trust the source of this workbook, click Yes.

I have three users that all use the same network share to save and edit excel workbooks. Every couple of days they have a file that gives this error when they open a workbook. None of the users have left the workbook open over night. Occasionally, there is an error that won't allow any of them to save or exit the file either. I always end up saying yes to trust the source, save it as a different file name, and put it back up on their share to use. This is a quick fix but what is the reasoning for files becoming corrupted so often? Is it something they are doing?

Thanks

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