This Knowledge Base article only applies to out-of-box (OOB) workflows.
When a workflow is started, it is then automatically canceled by the system account in Microsoft SharePoint 2010.
Figure 1 shows the workflows that were started but were automatically canceled as you can see in the Status column. Figure 2 shows the history entry for one of the canceled workflows. Notice that the Event Type indicates an Error and the Outcome indicates Access Denied.
The cause is currently unknown. The Microsoft Online Services Support Team is in the process of engaging CSS to determine the root cause and find a permanent fix.
Browse to the affected SharePoint site.
Click Site Actions, and then click Site Settings.
If the affected site is a sub-site instead of a top-level site, in the Site Collection Administration section, click Go to Top Level Site Settings.
Click Site Collection Features.
Deactivate the Workflow feature.
In SharePoint Designer, open the root of the site collection.
Go to Workflows.
Remove the Workflow in question (for example, Approval - SharePoint 2010).
In SharePoint, in Site Collection Features, reactivate the Workflow feature.
Confirm that the workflows are functioning as expected.