My dog is scooting and I know it’s not worms as I keep him on a good worming schedule. What could be the cause?
By scooting I assume you mean dragging his bottom on the ground.
There are a few common causes. Apart from worms, the most common cause is anal gland problems which you may not be able to ascertain just by looking. You could also check under his tail to see if there is any red or inflamed areas as some dogs, particularly with wrinkly skin or curly tails may get a dermatitis (inflammation of the skin) around their bottom. In both cases your best point of call is your veterinarian for treatment.
There are some other less common causes, all of which a veterinarian needs to diagnose.
Occasional scooting can be caused by a foreign object such as grass caught in their sphincter which you can attempt to remove yourself. Or if concerned take your dog to your vet where they can do this for you.