New here and looking for help with a magazine subscription list. Trying to figure out how to highlight the customers that are already in the sheet if enter them again (renewal). Our list is like so....
ColA ColB ColC ColD ColE ColF
First Last 123 Ave City State Zip

Is there a way to highlight the row if the info on ColA, ColB, ColE, and ColF all match? Sometimes the Street info is abbreviated or entered PO Box instread of P.O. Box and they wind up on the list a second time. Any help would be greatly appreciated. Kind of a newbie here.