I have a standard Tasks list that I want to trigger the out-of-the-box Approval
Workflow. I set up the Approval Workflow with the following:
-Task List: New Task List (This creates a 'Task Approval Tasks' list)
-Name: 'Task Approval'
-History List: 'Workflow History'
-Assign tasks Parallel.
-Approvers: Myself
-Everything else was left unchanged. This allows ths workflow to be manually
started.

I invoke this workflow on a list item on the Tasks list. The workflow status
says 'In Progress' (as it should). I click the links to approve this workflow.
It comes back to the 'Workflow Status' page as Completed, but the Workflow
History does not include the completion. Also, when I return to the original
Tasks list, the Workflow Status still says 'In Progress' (It should say
'Approved'). BTW, the 'Task Approval Tasks' list says the Approval task is
Completed.

In the past, I've been able to add the OOB Approval Workflow to any custom
list. This just happens to the Tasks list.

Any ideas as to why this occurs?