What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
I have checked your form http://www.jotform.us/form/60493704719158 and I can see the error you're mentioning when trying to download submissions as PDF.
I will forward this thread to our second level so our developers will investigate and resolve the problem, we will notify you via this thread as soon as we receive news regarding this matter.