Exchange OOF sending external is not working for single user. We have migrated from Exchange 2003 to Exchange 2007 a few months ago. Outlook client on local computer is 2003. Outlook client in Citrix environment is 2003. Employee bounces back and forth between local client and Citrix. We are also using OWA 2007. Employee's OOF does not reply to internal or external emails. Other employee's Out of Office notifications work fine.