Put an X in a cell if there is Text in a Range of Cells. Leave blank if not.

The Cell count say Star, Certificate, Rookie or be blank.
If the K10:S10 says either Star, Certificate or Rookie, I want an x in cell AC10, if nothing, leave it blank.

Here is what I have so far
=IF(K10="STAR",)OR(O10="Certificate","X"," ")