Annoying Word ('04) problem with line breaks. Help!

[Astral Cars]

I've attached an image of what is happening. I randomly get these lines that go across the page sometimes when I hit return. Originally a series of asterisks would turn into them, but I could simply click the little lightning bolt auto correct thing and change it back. Now I'm getting these lines randomly and there's no apparent way to get rid of them; the lightning bolt does not show up when I hover over it. Does anyone have any ideas? I'd rather not turn in a paper with screwed up formating like this. Thanks.