When web apps secure mode is enabled, WorkflowGen will try to store web form runtime temporary files inside a GUID sub-folder (36 characters length) for the current action.
In some cases, the generated path might exceed the Windows maximum path length of 260 characters. (See the Maximum Path Length Limitation section in the Naming Files, Paths, and Namespaces Microsoft article for more information.)
There are two workarounds:
Disable web apps secure mode in the Security section on the General tab in the Configuration Panel.
Make sure the web form storage path (e.g.
\\SERVER\SHARE$\WfApps\WebApps\eFormAspx\App_Data) is as short as possible.