If you get this error, it generally indicates that you have really long lines in your latex file.
If you're using Emacs, you can easily fix this in one of two ways:
- Press M-Q in each paragraph.
- Hit ctrl-space at the beginning of your text. Go to the end of your text and type M-x fill-region
To avoid problems with this in the future, see our answer on How to set Auto Fill Mode by default