Exchange Allow Relaying

If you have a server that needs to send email to any and all destinations, you need to create a new Receive connector, and manually add host’s addresses.
Then you need to use power-shell to run this command against that particular Receive connector.

Get-ReceiveConnector "" | Add-ADPermission -User "NT AUTHORITY\ANONYMOUS LOGON" -ExtendedRights "ms-Exch-SMTP-Accept-Any-Recipient"

Verify old and new Folder Redirection targets point

PolicyVerify old and new Folder Redirection targets point to the same share before redirecting
Category PathComputer Configuration\Administrative Templates\Windows Components\File Explorer\
Supported OnAt least Windows 7 or Windows Server 2008 R2
Registry KeyHKLM\Software\Policies\Microsoft\Windows\Explorer