Send Email

I need to send mail from  say 'AKS-DoNotReply@HSBC.com'... but when am trying to send its saying "No valid recipients resolved". but from other mail id am able to send ..
My doubt is AKS-DoNotReply@HSBCcom mail id needs to be created which Appian guy needs to create. Or is there some configuration am supposed to make if so please guide with steps.
Note: Am using Custom Sender to send Email.
 

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