Adobe LiveCycle Reader Extensions ES Version 8 - res problem

We have been using Adobe LiveCycle Reader Extensions ES Version 8 to create forms that are used internally within the business, but also externally for customers to complete and email back to us.

We haven't created new forms for a while, but now when we log into the LiveCycle Reader Extensions Server User Interface and try to res a form, it just times out.

It gets to the process status, and then just stalls and says that it's downloading, but nothing actually happens. Any ideas on a fix?