What are these black lines?

Can someone tell me what the black lines are in this picture of my floor plan? I noticed a couple of them when I pulled the view back in floor plan, but now they're multiplying. I saved my work, thinking it might be some kind of Windows issue, but upon opening again....there they were.

I can't select them and can't seem to find anything in the Help menu regarding black outlines.

Thanks!

I have never seen anything like that, did you maybe copy and paste some CAD lines?

Thanks for the input. I'll try tech support and reply here if/when I get an answer.

Carol

In my existing plan, I can turn off their display by selecting Tools> Display Settings> Display Options and unchecking the Disp (Display) column for the DEFAULT CAD LAYER.[/I][/FONT]

If anyone else experiences it.