Error: New or copied formulas cannot be saved (due to shared worksheet).

Error:

New or copied formulas cannot be saved while the file is being shared. Show this message in the future?

Cause:

This error occurs when saving a formula in a shared worksheet. The formula added has been saved but will not be visible to any other users who currently have the shared workbook open. This does not affect the functionality of the shared workbook.

Solution:

Other users may view the formula by exiting their copy of the workbook and reopening it.