Is it:
She thought it must be stuck, a problem that was not uncommon in her own Orderhouse.
Or:
She thought it must be stuck, a problem which was not uncommon in her own Orderhouse.
Grammar Girl is not helping me.
I think it is “that” instead of “which.”
UPDATE: Looking at this post on 7/25/2013, I now think it should be “which” instead of “that.”
I learned this last year but can’t recall it at the moment. it had something to do with an antecedent, I think. Those materials are now in bags in the living room with no ope of seing sunlight before my glorious TWO WEEK Christmasn break. :P
You sound like a govt employee. :p