Chances are you have your Flat File Connection Manager setup incorrectly. When you go to Preview, does your data line up? If not, make sure you are accounting for the End Of Line characters in your column-definitions.
If you're stuck zip your SSIS Package and a few lines of your data file to this thread and I'll have a look.
There are no special teachers of virtue, because virtue is taught by the whole community.
--Plato