I think that in addition to Corion's advice, a Short, Self-Contained, Correct Example would be very useful here. Reduce your script to the bare minimum needed to reproduce the error by removing pieces of code bit by bit: if the problems goes away, then the problem was in that piece of code, and if the problem stays, you know that piece of code wasn't relevant. Doing this will help you, as it will narrow down the issue to the part of the code that is causing the problem, and it well help us, because it'll give you a short piece of code to post here that we can download and run to try to reproduce the problem.