3649886 - SMTP Mail Server Configuration fails with error while using the "Proxy Type" as "On-premise"

When user configures the SMTP Mail Server as per SAP Help document Configuring SMTP Mail Destination, while testing SMTP Server Configuration in SAP Build Process Automation, it results in below error:

"Email could not be sent due to an error on the SMTP server."

"Image/data in this KBA is from SAP internal systems, sample data, or demo systems. Any resemblance to real data is purely coincidental." 

SAP Build Process Automation

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