Symptoms
We have two environments, Production and Lab. Both use the same mail server. On Production, we can send from any email address in email wizard. On Lab I have to stick to authenticated email addresses or get the error "SourceCode.Workflow.Common.EWS: The e-mail address blahblah@k2.org does not have 'send on behalf of' permissions on Exchange".
Diagnoses
Can someone direct us on how to change configuration to allow sending from any email address?
Resolution
Using the ConnectionStringEditor, the customer was able to add the SMTP connection strings to the LAB environment, which resolved the issue.