None of the colors will print on the left side approximately 1 inch from margin. It seems cleaning is the best solution so far which I will try tomorrow when I am onsite. If the developer does need to be replaced how tough of a job is this? The client has 2 identical units and we were going to swap the developer (as one unit if possible) but it was getting too involved for the time we had. I also can't seem to find Dell printer service manuals - do they actually exist?