There are two different PINs entered in different places.
The 6 digit IP PIN is best entered in "other tax situations" as described below. An IP PIN is only issued to confirmed victims of identity theft.
Separately, EVERYONE needs a 5 digit e-filing PIN, which is a required, though weaker, form of identity confirmation. You choose a 5 digit e-filing PIN the first time you e-file, and use it every year thereafter. If you don't remember it, you can use your AGI (adjusted gross income) from last year's tax return.
