I rarely run into this with rolls on the 8400.
When I have, what I like to do is load the paper up as normal and instead of only partially lifting the release lever when instructed, lift it all the way and pull the leading edge of the paper to the floor.
Once here, I will grab the roll and spindle and manually wind it up slowly, trying to keep it pretty straight.
This seems to work pretty well the few times this does seem to happen.
For some more details: what paper are you using? Is the printer giving you a paper skew error after it tries to initialize and right before it normally asks you to select the media type on the LCD?