Ms.Excel Tips Lock and Protect Cells Containing Formulas
You may want to let users change cells containg data without providing them access to change formulas. You can keep cells containing formulas under lock and key without having to protect your entire sheet or workbook.
When we create a spreadsheet, most of us need to use formulas of some sort. Sometimes, however, you might not want other users to tamper/ delete/overtype any formulas you included on your spreadsheet. The easiest and most common way of barring people from playing with your formulas is to protect your worksheet. However, protecting your worksheet doesn't just prevent users from tampering with your formulas, it also stops users from entering anything at all. Sometimes you do not want to go this far.
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