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Sending ERP user with region data
1. Make sure the 'Object' field in transaction /PACG/ECM_P_GR is set to 'Address region'
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2. Make sure the testing user has a region maintained in transaction PA30 (infotype 'Addresses')
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3. Make sure this region has been sent to SAP FSM before.
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4. Send a user with transaction /PACG/ECM_USERMASTER – User.
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5. Go to WE05 and find an idoc of type /PACG/ECM_ITYPE_USER. The region data can be found in the 'regiondata' segment
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6. The region field of Person, type ERPuser ID is updated with a region.
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7. Send an employee object with transaction /PACG/ECM_EMPL. An idoc of type /PACG/ECM_ITYPE_USER is generated, also holding region segments.
8. The final result : 
Additional docs: https://proaxia-prod-doc.atlassian.net/wiki/spaces/PFCC/pages/70221952/Transferring+regions+from+SAP+to+FSM can be found in FSM user master data.