How many times was Dale Cooper Stabbed at The Black Lodge?

Twice by Windom Earl - The first time he was "disguised" as Laura Palmer screaming at him and the second time he did it BOB was sufficiently pissed off that he killed Windom.That's what he gets for screwing up BOB's plan to possess Coop. You can see it was really Windom, not Laura the first time - there is a split second shot of it. Evidently you don't need wigs or makeup to disguise yourself in the Black Lodge.