If a cell contains a formula that results in an error, a triangle (an error indicator) appears in the top-left corner of the cell. You can prevent these indicators from being displayed by using the following procedure.
Cell with a formula problem
In Excel 2016, Excel 2013, and Excel 2010: ClickFile>Options>Formulas.
UnderError Checking, clear or Check theEnable background error checkingcheck box.
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