SharePoint 2010 custom workflow resulting in "heavy load"

I have a custom built state machine workflow using visual studio 2010. This workflow is started by the user creating a new list item on a moderated list. This list item has two checkboxes. Once the list item has been approved an email is sent to the requester, a task is created for each checkbox ticked, the work flow waits for all tasks to be complete, and then the workflow finishes. The 2 tasks are created in parallel with if-logic to determine if the task should be created.

There are 4 possible scenarios with this configuration:

1. no check boxes checked - working fine
2. both check boxes checked - working fine
3. the first check box checked - working fine
4. the second check b开发者_如何学Goox checked - "Due to heavy load, the latest workflow operation ..." this occurs after the approval, and before the email to the approver.

I have allowed the workflow to wait for 10+ hours with no change to the "heavy load" message and the workflow not going forward. I am running a local dev standalone SP2010 instance. Any thoughts?

---

Other people have have the same problem when placing approval start tasks in parallel processes. See http://social.technet.microsoft.com/Forums/en-US/sharepoint2010customization/thread/d6340097-9de3-4f42-a690-ed1f2b7597e4/

It may be a bug causing a locking problem.

The hack to get it to work would be to run them after each other.