If you can otherwise access documents and other users can edit this spreadsheet, this may occur where the spreadsheet itself has macros enabled and the macros have underlying business rules which limit user access. These rules are attached to the document itself, so this is not a specific FYI issue. A macro-enabled spreadsheet like this may have come from providers such as HowNow.
If you need to edit the document:
- Export the spreadsheet from FYI
- Open the spreadsheet
- Select 'save as' and save it as .xlsx.
- Then re-import the document into FYI and you should now be able to edit the document.