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Excel worksheet formulas not working when sheet is protected

I have an Excel worksheet containing checkboxes that control the contents of another cell containing the formula, as well as other cells requesting user input. I need to post this worksheet on a webpage for users. The problem is when I protect the worksheet, the formulas no longer work. The checkbox cells, the formula cells, and the user input cells are unlocked. The user input cells work when protected, but the checkbox and formula cells no longer function when Protection is enabled. How do I protect the worksheet and have the formulas still work?