- Check if your workbook is being shared or stored in a SharePoint server.
- Make sure that you have correct version permissions to be able to edit a workbook.
- Check if there are any active worksheet protection options enabled in the workbook.
- Verify that your document does not have read-only attributes.
- Check if your document is locked for editing because another user is editing at the same time.
- Disable VBA projects if its a macro-enabled workbook.
- Make sure that you have the right permission level to make changes to the Excel file.