Conditional Formatting using Match

welcome to the forum. this is for column E:O. select the range you want to apply to (say from E2:O10)
go to Home tab -> Conditional Formatting -> New Rule -> Use a formula to determine which cells to format -> Format values where this formula is true:
=COUNTIF($B:$B,E2)
format desired color

for column B, do the same steps but for B2:B10 for eg:
=COUNTIF($B:$B,B2)>1

if i guessed it wrongly, do upload an excel sample so that we do not have to manually key in your data to do a testing.

input the desired results so that we don't have to second-guess if what we are doing is correct or not. you may look at my signature to upload an eg that is easier to understand.

the upload attachment must be done by going to Go Advanced. click on Manage Attachments. Choose file, upload and close the window.