When you create a new resource mailbox by using Exchange Admin Center (EAC) in a Microsoft Exchange Server 2013 environment, the resource mailbox is not stamped with the SMTP address from the email address policy. Additionally, the Automatically update email addresses based on the email address policy applied to this recipient option is not select in the properties.
NoteThe Automatically update email addresses based on the email address policy applied to this recipient check box is selected to have the recipient's email addresses automatically updated based on changes made to email address policies in your organization. This box is selected by default.
NoteThe Automatically update email addresses based on the email address policy applied to this recipient check box is selected to have the recipient's email addresses automatically updated based on changes made to email address policies in your organization. This box is selected by default.