Consider the following scenario:
You create a workflow in SharePoint Designer 2013 by using the SharePoint 2010 Workflow Platform type in SharePoint Online, SharePoint Server 2013, or SharePoint Server 2010.
Within the workflow, you have an impersonation step. The impersonation step is configured to do the following:
Return a field that has a value other than As a string.
Use the value in that field to change permissions
The field that you are trying to collect information from contains user accounts.
In this scenario, when you run the workflow, the workflow does not finish, and the status is displayed as Error Occurred.
To resolve this problem, configure the Return field as value within the impersonation step to As a string.
This problem occurs if the person or group column allows multiple selections and if the value in that column is returned as something other than As a string. This configuration causes the workflow to fail.
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