If you are using Excel 2013, I'm sure you must have encountered be careful Excel warning. When you try to save a workbook, suddenly a pop-up appears saying 'Be careful! Parts of your document may include personal information that can't be removed by the Document Inspector.'
It is definitely annoying, but also this feature is necessary to prevent unintended personal information leakage. There is always a balance between ease of use and privacy. If you are sharing a workbook and don't want the recipient to know who wrote the original document, such privacy options come very handy.
The dialog pop-up is actually not an "Error", rather it is informational, which is less severe than an error. It just says there "may" be personal information in the file. But unfortunately Excel doesn't tell us if it is included or not. Moreover it also doesn't tell us what and where this alleged personal information is.
If you are planning to share the workbook, it is always a good idea to run the Document Inspector to review the workbook for hidden data or personal information that might be stored in the workbook itself or its properties (metadata).
Coming back to the be careful Excel warning, I was not able to find an actual solution; but there is always a short-cut.
If you are getting this be careful Excel warning, go to File<Options
In the options, go to the Trust Center and open the Trust Center settings:
In the Trust Center go to the Privacy Options and click Remove personal information from file properties on save.
Hope this will solve your be careful Excel warning issue. If you have any other solution to this be careful Excel warning, please share with us in the comment section below.