I am getting the following message in the event log when trying to run a Workflow Service Task from Forms. I went ahead and add the recommended configuration to the Workflow application in IIS and now forms just says "Access Denied" when trying to run the task.

: System.ServiceModel.ServiceHostingEnvironment+HostingManager/62476613
 Exception: System.ServiceModel.ServiceActivationException: The service '/Workflow/api' cannot be activated due to an exception during compilation.  The exception message is: This collection already contains an address with scheme http.  There can be at most one address per scheme in this collection. If your service is being hosted in IIS you can fix the problem by setting 'system.serviceModel/serviceHostingEnvironment/multipleSiteBindingsEnabled' to true or specifying 'system.serviceModel/serviceHostingEnvironment/baseAddressPrefixFilters'.
Parameter name: item. ---> System.ArgumentException: This collection already contains an address with scheme http.  There can be at most one address per scheme in this collection. If your service is being hosted in IIS you can fix the problem by setting 'system.serviceModel/serviceHostingEnvironment/multipleSiteBindingsEnabled' to true or specifying 'system.serviceModel/serviceHostingEnvironment/baseAddressPrefixFilters'.
Parameter name: item