Those buildings are not from our scenery, they look like the default ones.
Check that you don't have another scenery for Chicago, or another AFCAD in conflct for O'Hare, from another scenery that hasn't been removed.
Also, if you have Flytampa Midway, check that you don't have the kord_tweak.bgl file, which is only needed for the default KORD.
