When trying to access the 'Forms' tab of a PeopleSoft job the following message appears in a popup box:
Failed to deserialize GetCertificate request data
<Please see attached file for image>
CauseUserInterface isn't configured to view PeopleSoft ERP Forms.
From the Documentation for Installing the UserInterface (Administration Guide > Installation > New Installation > Installing the UserInterface > For either platforms it's Step 4):
In order to use PS ERP Forms, the PeopleSoft Java Object Adapter and specific Java classes (UCXJPS84.jar) are required.
Adjust the entry "classpath" (psjoa.jar) in the INI file of the UserInterface, as needed.