Today I tried to publish a SharePoint Designer Workflow and received the following error:
“Errors were found when compiling the workflow. The workflow files were saved but cannot be run”
The error detail was also not very informative:“Unexpected error on server associating the workflow”
I found a lot of possible reasons and suggestions how to fix the issue, but nothing worked for me.
Finally I looked at the workflow settings in one of my lists and found many old workflow instances. After deleting all old and unused instances, the workflows could be published again.