Error AHD04646 when trying to delete a workflow task in a Problem ticket

Steps to Reproduce:

1. Go to Administration -> Service Desk -> R/I/P -> Areas

2. Right-click on any entry such as Applications and select Edit

3. Go to Workflow -> Problems tab

4. Click on Use Classic Workflow

5. Set Task to Start Approval and check off (enable) Deletable.

6.  Save changes.

7. Create new problem ticket and set Category to category updated in step 2.

8. Save ticket and note ticket number.  Close ticket window.

9. Enter ticket number on Go field (top right)

10. Go to Additional Information -> Workflow Tasks tab

11. Right-click on task and select Delete

12.  Error shows up.  See screenshot.

13. Try step 11 again and this time it works.