in general there are 2 potential causes for this
1. Text pre-formatted cells
If cells have been pre-formatted using format code
@ (Text) disables input recognition (formulas, dates) and takes the input “as-is” and
= no longer functions as an indicator for “the following is a formula” but is taken literally.
- Select the cell contain the textual formula
CTRL+M (removes the text format)
- Perform any edit of the formula (e.g remove and re-add the closing parenthesis
) of the formula)
Do not pre-format cells with format code
@, if you intend to use formulas.
View -> Show Formula set
This won’t apply in your case, since this appears to be a global setting and hence you’d see it in all sheets or none of you sheets.