It sounds like you may be experiencing some issues with Excel not displaying the file portion of the control ribbon and not saving spreadsheets correctly. One possible solution is to try opening a new workbook in Excel and then opening the file from your folders. This may allow you to save correctly and get the "file" back in the ribbon. Another possible solution is to check for hidden sheets or disable hardware acceleration. For more information on troubleshooting why Excel doesn't save changes, see the following article: Troubleshoot why Excel doesn't save changes.
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