550 5.7.1 RESOLVER.RST.AuthRequired; authentication required

Question

Following error i get  when sending mail to SharePoint mail enabled library. It create contac  with  non ruted domain. Domain is not public. Let say that ending of domain is LOC. So it is not
registered public domain…
 And it is A  contact, not Distribution group. Let put it , that that name  of the contact is : [email protected]
I have setup Hybrid. All Exchange server s  are Exchange 2013 CU5.
To make it work, I have tried to send mail, to that library through share mailbox or transport rule…. Every time I send mail from outside organization or from mailbox, that is hosted in O365 I get following error :
[email protected] <- I did use   email of shared mailbox , but that is returned
Your message can't be delivered because delivery to this address is restricted.
Diagnostic information for administrators:
Generating server: MBX01. noreg.loc
[email protected]
Remote Server returned '550 5.7.1 RESOLVER.RST.AuthRequired; authentication required'
Massage tracking loge, gives me following error :
RunspaceId              : 9fd72017-0941-42f0-8625-b58b1c79b367
Timestamp               : 6/12/2014 3:30:03 PM
ClientIp                :
ClientHostname          :  MBX01
ServerIp                :
ServerHostname          :
SourceContext           :
ConnectorId             :
Source                  : ROUTING
EventId                 : FAIL
InternalMessageId       : 20190641259111
MessageId               : <[email protected]ngelabs.com>
Recipients              : {[email protected]}
RecipientStatus         : {[{LRT=};{LED=550 5.7.1 RESOLVER.RST.AuthRequired; authentication required};{FQDN=};{IP=}]}
TotalBytes              : 10261
RecipientCount          : 1
RelatedRecipientAddress :
Reference               : {<91a7f625-60e6-4070-a834-b120d77d4c41@ MBX01.noreg.loc>}
MessageSubject          : test 1111
Sender                  : [email protected]
ReturnPath              : [email protected]
Directionality          : Incoming
TenantId                :
OriginalClientIp        :
MessageInfo             :
MessageLatency          :
MessageLatencyType      : None
EventData               : {[DeliveryPriority, Normal], [ExternalOrgIdNotSetReason, ]}
Additional Info   : 
Customer has internal domain whom  FQDN is noreg.loc. They have SharePoint  farm.  Farm has several  mail enabled document libraries.   Email enabled libraries has  FQDN  of sharepoint.noreg.loc.  They have  about
100 of those mail enabled libraries.  When library is crated it create contact, that is
[email protected],
[email protected] , and so on...
Internal users can send  mail to that SharePoint library, works.  It has stopped working for those  whose  mailbox »user« is moved to  Office 365.
Now i have a problem. Because domain noreg.loc and sharepoint.noreg.loc is publically non-rutable domain, i do not wont to change  all emails addresses of library, I will  or I`m trying to do workaround.
First detailed  of contact :
[email protected]
External SMTP : [email protected]
Alternate email :
[email protected],
[email protected]
I can not use distribution group, and sync it to office 365. Because expansion of members in that distribution group, will happened  in Office 365 Exchange server. That will end up with error non existing domain for
lsharepoint.noreg.loc.
 So I have tried with shared mailbox, that has setup forward to contact
[email protected].  I know that shared mailbox, has pickup mail, because, I have forget to set it, that every one can send to these recipient.  When that is setup,  mail is received, and transferred to  [email protected]
, where it failed with error  authentication required.  Server that   send  error is Mailbox server “Exchange 2013”.
I will try to setup classical mailbox, with forward to contact, but that would use local licences, that I do not wont.
I need to setup  default receive connector on MBX server to allow  no-authenticated “server”  to relay, which I thing is security problem.
I do not understand why would sending mail to contact, required  authentication 

Answer 1

Hello,
Please try to use telnet command to send message to sharepoint to check the result.
Please create a new receive connector, and then enable "anonymous users" on a new receive connector to check the result.
Cara Chen
TechNet Community Support