Const strValidUser = "andermc";  '<- My NT/Exchange username 
Set objOutlook   = CreateObject("Outlook.Application")
Set objNS        = objOutlook.GetNamespace("MAPI")    
Set objRecipient = objNS.CreateRecipient(strValidUser)
    objRecipient.Resolve
    
If (False = objRecipient.Resolved ) Then '<- not return value from above!
    'need to exit nicely