From the Home tab, click on Conditional Formatting, New Rule
Select “Use a formula to determine which cells to format”
And then type the formula
(where Column C is the column that we are comparing with and E23 is the first cell of the data that we have highlighted. This formula works for any comparison of data between 2 columns – you just have to adjust the Column that you are comparing with and adjust the cell of the first entry of your data)
Click on the Format button on the Conditional Formatting box.
Choose the format of the font if the selection differs from the entry you are comparing with. In this case, any entries in column E that don’t match the corresponding entry in column C will be red and bold.
Click on OK
Click on OK again