Forum Discussion
Group Email by Domain Users
Either Dynamic DG or O365 Group would do, the problem is that *everyone* can send messages to it once you toggle the flag. To restrict this, the best option would be to use Mail flow rules, as they give you a lot of freedom in terms of conditions you can use to "match" the sender.
What you are asking for is the default behavior in O365, for both "traditional" distribution groups and "modern" Office 365 groups. There's no need to configure anything.
VasilMichev I continue to get NDRs when sending a message to one of these groups. It is just a Unified or new distribution group.
Here is the distribution list config in case I have inadvertently configured it incorrectly.
I appreciate the help
RunspaceId : 2a2eaf8e-7422-4792-bd80-a6bb8a520a3d
AccessType : Private
AuditLogAgeLimit : 90.00:00:00
AutoSubscribeNewMembers : True
AlwaysSubscribeMembersToCalendarEvents : True
CalendarMemberReadOnly :
CalendarUrl : https://outlook.office365.com/owa/?pat
h=/group/*******/calendar
Database : NAMPR19DG029-db093
ExchangeGuid : 78c028d9-4bb9-4760-bcc2-99de1e5902a0
FileNotificationsSettings :
GroupSKU : Default
InboxUrl : https://outlook.office365.com/owa/?pat
h=/group/********/mail
IsExternalResourcesPublished : True
IsMailboxConfigured : True
Language : en-US
MailboxProvisioningConstraint :
ManagedByDetails : {*****}
Notes :
PeopleUrl : https://outlook.office365.com/owa/?pat
h=/group/******/people
PhotoUrl : https://outlook.office365.com/EWS/Exch
ange.asmx/s/GetUserPhoto?email=*******
ServerName : mn2pr19mb3007
SharePointSiteUrl :
SharePointDocumentsUrl :
SharePointNotebookUrl :
SubscriptionEnabled : True
WelcomeMessageEnabled : True
ConnectorsEnabled : True
IsMembershipDynamic : False
Classification :
GroupPersonification :
YammerEmailAddress :
GroupMemberCount : 17
MailboxRegion :
GroupExternalMemberCount : 0
AllowAddGuests : True
WhenSoftDeleted :
HiddenFromExchangeClientsEnabled : False
ExpirationTime :
DataEncryptionPolicy :
ResourceProvisioningOptions : {}
ResourceBehaviorOptions : {}
ServiceEndpointUris : {}
SensitivityLabel :
InPlaceHolds : {}
EmailAddresses : {smtp:*******
, SMTP:*******}
PrimarySmtpAddress : ********
Name : all_4c001ab1-f883-41b9-8fc9-26765a852f
b9
DisplayName : All Staff
RequireSenderAuthenticationEnabled : True
ModerationEnabled : False
SendModerationNotifications : Always
SendOofMessageToOriginatorEnabled : False
BypassModerationFromSendersOrMembers : {}
ModeratedBy : {}
GroupType : Universal
IsDirSynced : False
ManagedBy : {****}
MigrationToUnifiedGroupInProgress : False
HiddenGroupMembershipEnabled : False
ExpansionServer :
ReportToManagerEnabled : False
ReportToOriginatorEnabled : True
Description : {}
BccBlocked : False
AcceptMessagesOnlyFrom : {}
AcceptMessagesOnlyFromDLMembers : {}
AcceptMessagesOnlyFromSendersOrMembers : {}
AddressListMembership : {\Default Global Address List,
\GroupMailboxes(VLV), \All
Recipients(VLV), \Groups(VLV)…}
AdministrativeUnits : {}
Alias : all
OrganizationalUnit : nampr02a003.prod.outlook.com/Microsoft
Exchange Hosted Organizations/******
CustomAttribute1 :
CustomAttribute10 :
CustomAttribute11 :
CustomAttribute12 :
CustomAttribute13 :
CustomAttribute14 :
CustomAttribute15 :
CustomAttribute2 :
CustomAttribute3 :
CustomAttribute4 :
CustomAttribute5 :
CustomAttribute6 :
CustomAttribute7 :
CustomAttribute8 :
CustomAttribute9 :
ExtensionCustomAttribute1 : {}
ExtensionCustomAttribute2 : {}
ExtensionCustomAttribute3 : {}
ExtensionCustomAttribute4 : {}
ExtensionCustomAttribute5 : {}
GrantSendOnBehalfTo : {}
ExternalDirectoryObjectId : 4c001ab1-f883-41b9-8fc9-26765a852fb9
HiddenFromAddressListsEnabled : False
LastExchangeChangedTime :
LegacyExchangeDN : /o=ExchangeLabs/ou=Exchange
Administrative Group (FYDIBOHF23SPDLT)
/cn=Recipients/cn=0c641af02a094c2eb7b1
a3ce470a8036-all_491d5d3
MaxSendSize : 35 MB (36,700,160 bytes)
MaxReceiveSize : 36 MB (37,748,736 bytes)
PoliciesIncluded : {}
PoliciesExcluded : {{26491cfc-9e50-4857-861b-0cb8df22b5d7
}}
EmailAddressPolicyEnabled : False
RecipientType : MailUniversalDistributionGroup
RecipientTypeDetails : GroupMailbox
RejectMessagesFrom : {}
RejectMessagesFromDLMembers : {}
RejectMessagesFromSendersOrMembers : {}
MailTip :
MailTipTranslations : {}
Identity : all_4c001ab1-f883-41b9-8fc9-26765a852f
b9
Id : all_4c001ab1-f883-41b9-8fc9-26765a852f
b9
IsValid : True
ExchangeVersion : 0.10 (14.0.100.0)
DistinguishedName : CN=all_4c001ab1-f883-41b9-8fc9-26765a8
52fb9,OU=*****,
OU=Microsoft Exchange Hosted Organizat
ions,DC=NAMPR02A003,DC=prod,DC=outlook
,DC=com
ObjectCategory : NAMPR02A003.prod.outlook.com/Configura
tion/Schema/Group
ObjectClass : {top, group}
WhenChanged : 12/11/2020 11:32:43 AM
WhenCreated : 12/3/2020 11:58:37 AM
WhenChangedUTC : 12/11/2020 4:32:43 PM
WhenCreatedUTC : 12/3/2020 4:58:37 PM
ExchangeObjectId : ebc6953a-f46a-4aed-ab54-ea71ca494863
OrganizationId : NAMPR02A003.prod.outlook.com/Microsoft
Exchange Hosted Organizations/***** - NAMPR02A003.pr
od.outlook.com/ConfigurationUnits/*****/Configuration
Guid : ebc6953a-f46a-4aed-ab54-ea71ca494863
OriginatingServer : SN6PR02A03DC004.NAMPR02A003.prod.outlo
ok.com
ObjectState : Changed
I should also note that the messages being rejected are being sent by an automated system sending via Sendgrid.
Based on your original question, I thought you *didnt* want external messages to the group? If you do want to enable this, toggle the RequireSenderAuthenticationEnabled flag. If you want to only allow messages from specific external addresses, best create a Mail flow rule.
VasilMichev Appreciate the help. Some of your questioning led me to look into some items further.
What I have is several "external" systems that I want to be able to email distribution lists/groups. Those systems do not authenticate but rather send via SendGrid.
For now I think I have it accomplishing what I wanted by allowing "external" senders, but then creating a dynamic distribution list with all users/groups and then it has allowed the message to be sent.
I'm not sure if this is the best way to accomplish this or not, but for now, it seems to be working.
