Excel formula displays formula rather than result

"Edit your formula and be sure there isn't a ' before the = sign.

The cell may have been formatted as text before the formula was entered.
Select the cell, then right-click and select Format Cells. Format the cell as
General (on the Number tab), then click OK. Press F2, then Enter.

Another possibility is that you have accidentally toggled the view to
display formulas rather than their results. Pressing Ctrl + ` (backtick, found next to the left of the number 1 on US keyboards)
to toggle the
view back to normal"

"I just had this issue pop up, but only for a specific section of cells. I tried every trick in every book I could find online. End result that fixed the issue was this:

Highlight the affected cell.
On the function line near the top, select in front of your = sign starting your formula.
Hit the backspace key like you are erasing a space.

I know none of my formulas had a leading space, but for some reason, this fixed the display issue, even though when I hit the backspace key, nothing appeared to erase, shift or move.
I don't know why (Excel 2010) did this; there is no logical reason this happened in the first place, and certainly no reason this should have fixed it, but it did.
Also you may have to change your format from 'Text' to 'General' to get this to work as well."