Advanced and complicated architectural situation: Shared Service Application with Workflow ?

Question

Hi Forum,
I am currently encountering a peculiar situation in our SharePoint 2013 environment (Let's call it Farm-1), and I would really be thankful for your creative suggestions.
Whenever we create any simple workflow on our Farm-1, it NEVER worked, and we get the exception:
RequestorId: 26f1da47-f3e6-0816-0966-df958cd57c7d. Details: System.ApplicationException: HTTP 401 {"error_description":"The server was unable to process the request due to an internal error. For more information about the error, either turn on
IncludeExceptionDetailInFaults (either from ServiceBehaviorAttribute or from the <serviceDebug> configuration behavior) on the server in order to send the exception information back to the client, or turn on tracing as per the Microsoft .NET Framework
SDK documentation and inspect the server trace logs."} {"x-ms-diagnostics":["3001000;reason=\"There has been an error authenticating the request.\";category=\"invalid_client\""],"SPRequestGuid":["26f1da47-f3e6-0816-0966-df958cd57c7d"],"request-id":["26f1da47-f3e6-0816-0966-df958cd57c7d"],"X-FRAME-OPTIONS":["SAMEORIGIN"],"SPRequestDuration":["252"],"SPIisLatency":["1"],"Server":["Microsoft-IIS\/8.0"],"WWW-Authenticate":["Bearer
realm=\"73b2c214-338d-4c93-937f-5852744a020d\",client_id=\"00000003-0000-0ff1-ce00-000000000000\",trusted_issuers=\"00000005-0000-0000-c000- ---
I have seen a handful of posts suggesting running the User Profile service and its Synchronization.
Also, I have see the presentation of: Spencer Harbar and Wictor Wilén on: (http://channel9.msdn.com/Events/SharePoint-Conference/2014/SPC356) where at minute 28:00 an slide 40 stating that as a requirement: User Profile Service Instance and Service Application,
Users must be populated in the Profile store and have valid User Principal Name (UPN).
My question is:
On our environment (Farm-1) we are consuming the User Profile service application from other separate SharePoint 2013 environment? Any workaround?
We really do not want to set up another User Profile service application onto our environment (Farm-1), Any possible workaround to make the current shared User Profile sufficient to run the workflows correctly?
What can be done?
Thank You 

Answer 1

Hi ,
For troubleshooting this issue, let's verify the followings:
What action did you use in your workflow? Please test just using “Log to history list” action, compare the result.
Please go to Central Administration->User profile service application, check whehter the user that you run workflows has user profile in Manage User Profiles.
As you are using SharePoint 2013, what platform did you use when you created workflows? Please try to create a new workflow using SharePoint 2010 plaform.
Whether this issue occurred on all web applications in your Farm-1.
Please open a problematic site collection->Site settings->Manage site features, make sure the feature “Workflows can use app permissions” is activated.
If you met this issue only for SharePoint 2013 platform workflow, you can also try to re-register workflow service via Register-SPWorkflowService.
More information about register workflow service:
https://technet.microsoft.com/en-us/library/jj663115(v=office.15).aspx
Best Regards,
Wendy
Wendy Li
TechNet Community Support