schnuffichen wrote in linguaphiles 😯confused

French Negation... "ne pas un"???

For all my life (or at least, for all the 5 years in high school that I took French), I've been told that "ne... pas", if followed by a noun, requires "de" instead of the indefinite article.
So, you say "Je ne connait pas d'enfants."
(Which, come to think of it now, sounds off to me, too... but, you know, something to that effect.)

Howeverrrr... living in Montreal I encountered several signs like "Ceci n'est pas un parcours." at a road in front of a school. And a friend says things like "Je ne suis pas un expert."
In my French, it would have to be "Ceci n'est pas de parcours." or "Je ne suis pas d'expert(e)."

So, I was wondering...

Is this a Quebecois vs. French French (which is what I learned) thing?
Is it something special about "être"?
Did I learn it wrong all along?