can't delete tiles

[Nycdrama212]

i ran the search engine on here about 5 times and seem to be getting nowhere - i demolished brandi brokes house to rebuild it and there is a square literally of about 4 or 6 tiles that i can not build on to finish a second floor - i demolished the goth house and again found 2 tiles that i could not delete - i have tried every cheat and don't know why i can't get these stupid tiles to go away - please help - thanks

[simsample]

When you say demolished, do you mean that you demolished from neighbourhood view, or that you deleted everything from in the lot? If the latter, then make sure you've deleted the roof, and that there are no objects on any of the upper levels. If there are, you need to put in columns to be able to delete them. Also, try turning off the floor constraints (boolprop constrainfloorelevation false) and then levelling the affected area. If that fails, move the sim out and demolish the lot from the neighbourhood!

[gwillewyn]

Could be an invisible stuck object. It happens sometimes.
Try this item: http://www.moreawesomethanyou.com/smf/index.php?topic=1609.0