Tasmania's Education Department Secretary hasn't been able to say why a notification of sex abuse apparently disappeared down a so-called "memory hole".
A teenager complained about a teacher's grooming and subsequent abuse but wasn't offered any support during the two-year investigation.
Tim Bullard has been grilled on the failure at the Commission of Inquiry hearings in Hobart.
"Only by looking at the things that haven't worked are we going to inform our ourselves of how to place ourselves to do this properly in the future, all such matters as those in that email would now come to me."
He revealed 32 people have been removed or stood down from the relief teaching register over historical allegations.
There's been evidence this week of complaints going ignored while victims felt belittled and threatened.