Pooping in front of the door

1 year old, female. The cutest darn thing but she keeps pooping in front of the front door. Been to the vet and she's healthy. I clean the area with enzyme spray. I've also done bleach water, floor cleaner and dish soap as well. There is a clean litter box less than 5 feet away. There are 6 litter boxes in the house. She pees in the boxes just fine. What do I try next?