Error "Error publishing workflow. A duplicate content type "Nintex Task Outcome Content Type" was found."

Issue

When publishing a workflow that has a task action configured, in Nintex Workflow for Office 365, the workflow fails to publish and the following error occurs:

Error Code

Error publishing workflow. A duplicate content type "Nintex Task Outcome Content Type" was found. If the problem persists, contact Nintex support, and quote: Correlation ID: Tenant ID: Time (UTC):

Resolution

1. Open Site Settings and determine if a Nintex Task Outcomes content type is listed under both Nintex Forms for Office 365 and Nintex Workflow for Office 365.
2. Navigate up to the site from which these content types are inheriting. This is likely the top level site of the Site Collection.
3. Remove all of the Nintex Task content types.

Note: This may require deleting workflow tasks from the Workflow Task list, these can be restored after the bad content types have been removed.

4. Once all Nintex Task content types have been removed, open the Nintex Workflow designer on the top site of the Site Collection and publish/run a workflow with a configured task action (this will recreate the now missing Nintex Task content types correctly).