In general, IE is picky about the widths in some cases. I would take a step back and start with a blank content wrapper. Then add in the left column, right column, then content. See where it breaks in that process (my guess is the #content). Then for the div that breaks it, strip out all the css and add that in 1 line at a time. See what property seems to break it, then adjust it accordingly until IE renders it properly.