I'm not familiar with the tutorial in question, but if you go back over it and check each step very carefully, you will most likely find that you didn't follow it exactly.
The main problem with tutorials is that the reader needs to think like a computer. In other words, don't think - just follow instructions. Most people throw in their own changes as they go, either accidentally or on purpose. They jump ahead, make assumptions and so on. If you can force yourself to follow the steps precisely as they are set out, chances are it will work as advertised.
This is just general advice, of course - it applies to pretty much any tutorial.