Davide,
I wanted to provide some additional details. It seems that the issue has resolved itself after some time. I had some questions and observations:
-I have recently modified the session timeout to: 360 minutes (Nicholas suggested this due to the way our case managers use the front end)
If I re-installed the admin tools per your instructions, and immediately tried the "Submit New Tickets" feature from the same browser session, would the error persist until either I logout/login or the session expires after 360 minutes.
I am only asking as I noticed that when I left work and started testing from home (a different computer) I noticed that the feature was working even though no other changes were made?
Either way, I will check when I get back to the office and ensure all is well.
Thanks again for your help!
Eric Johnson