I have a Workflow that has stopped working. As far as I am aware there have been no changes made to either the Workflow or the SharePoint Farm.
If I select an item from the list the Workflow runs against and select Workflow I get a Correlation ID error. Used Merge-SPLogfile to get the log file and the error message reads :-
Application error when access /layouts/15/Workflow.aspx, Error=A response was returned that did not come from the Workflow Manager. Status Code = 200
Googling the error reveals a lot of issues when installing Workflow Manager but not how to resolve this issue on a mature system.
Any help greatly appreciated as always,