The ULS logs may have the following entries:
Note: This will also affect Sharepoint Designer Workflows.
soap:ServerServer was unable to process request. ---> Failed to publish workflow
In addition to the above solution, the following will need to be added to the web.config and OWSTIMER.exe.config files if workflows are stuck 'In Progress' after the updates.
<authorizedType Assembly="Microsoft.SharePoint.WorkflowActions, Version=220.127.116.11, Culture=neutral, PublicKeyToken=71e9bce111e9429c" Namespace="Microsoft.SharePoint.WorkflowActions" TypeName="*" Authorized="True" />
In some cases, the OWStimer.Config file will also need to be updated, the steps to perform this are mentioned in the above video