Issue

"An application error has occurred" error message on a call. 

Product

Programmable Voice 

Cause

An application error means that the code Twilio is attempting to fetch at the URL that you have specified on your servers is either unavailable or has errors in it. This code is being fetched based on the incoming URL that you have specified on your phone number or in your application for instructions on how to handle a call.

Resolution

To handle an error like this, you should view your Twilio account's Error logs in Console for details on the errors your application is running into.