Neil you need to use a queue, don't work directly from the file. As Bastiaan says, load all cases into the queue, then move the file or rename it so that it won't get picked up again tomorrow. Design the process to stop itself at 1800 (see process templates) and use the scheduler to restart it at 0600 the next day. If a new file has appeared, load it as before. If the new file could contain duplicate cases, then only add new cases to the queue.You've got my email Neil, so send me your design if you want.