Content
Tenant Allow/Block Lists
In Microsoft 365 Defender we have: Allowed and blocked senders and domains Connection filtering (IP Allow list - IP Block list) It is not clear for me what exactly does "Tenant Allow/Block Lists" (senders, spoofing, URLs, Files).
Replace an expired federation certificate
We have to recreate the Federated Trust since the self-issue cert expired. Runing Exhange 2016 Hybrid DAG with no mailboxes on prem. When we remove the federated trust will that affect access, users ability to log in to O365 online mailboxes until its…

(hr=0x80004005, ec=1142) when trying to migrate Exchange Server user
Hi, I want to do On-premise Exchange 2016 to 2019 Migration and Co-existence. I got this error when trying to migrate user from 2016 to 2019
How To Have Separate Email Signatures for Internal and External Emails
I am on Windows 10 through Outlook App email, and I would like to set a different signature for internal and external emails but cannot find how to do it. To be clear, I would like completely separate email signatures so I have my more formal one for…
A user in a distribution group cannot receive an email
Hello. Please help me figure out the problem. We have a hybrid environment that includes an on-premise server MS Exchenge 2016. There is a distribution group. Users are added to it. All users except one receive emails sent to this distribution…
SMTP protocol 587 does not work correctly
Hallo! After my manipulations with re-issuing the certificate, I encountered a problem connecting Outlook clients. When connecting to the mail server, I specify the following parameters: POP3 protocol port 995 + SSL/TLS encryption. SMTP protocol port 587…
The certificate is invalid or the revocation could not be verified
Hello! I am issuing a certificate for the Exchange server: I'm doing... Create a request for a certificate signed by a certification authority. I save it in .REQ format. I log into Active Directory Certificate Services (Microsoft) on my server. …
is there any way we can update offline addressbook for users from Exchnage Online Admin
i want to delete an object from on prem AD and want to create same at EXO . but i when users will send an email to old object guid it gives NDR that object not found in this domain just because of old guid id. here i want any option we can enforce users…
Exchange 2019 CU12升级到CU13前提条件检查不通过
在尝试将Exchange 2019CU12升级到Exchange 2019CU13的过程中出现以下报错: 多次尝试不成功
Quorum Type for 3 Node DAG with witness servers show as "Mejority"
Hi! Quorum Type for 3 Node DAG exchange 2019 with witness servers show as "Mejority". Is this Node mejority or File share mejority. Confused! Cheers Priya
How to authenticate outbound email with SPF, DKIM, and DMARC records in EXO?
How to authenticate outbound email with SPF, DKIM, and DMARC records in EXO?
There is no editor registered to handle this attribute type - Azure/Exchange/AD
Hi there, We have a local active directory synced to office 365/Azure. Originally our Outlook situation was hybrid but all of our mailboxes have been in the cloud for the last few years so we recently uninstalled our local Exchange server. …
unable to download
Hi All I am using exchange 2016 hybrid environment. All users are created in onprem and migrated to online. An external user is sending emails to our domain users. External email has images and outlook is not downloading those images automatically.…
451 4.4.397 Error communicating with target host. -> 421 4.2.1 Unable to connect -> SocketTimedout: Socket error code 10060'
Hope someone can help. We have 4 Exchange 2016 Servers, in 2 separate DAGS. Out of no where, one of the Exchange Servers will not connect to the smart host. The 3 other servers are fine. When checking the queue on the server, the error is: 451 4.4.397…
Query on Room mailboxes
Hi All we use exchange 2016 hybrid environment. we create room mailboxes in onprem using new-remotemailbox syntax. These room mailboxes are synchronized to Azure AD.Please correct me if i am wrong. Room mailboxes are by disabled in onprem AD. In Azure AD…
Install DKIM on 2 Exchange 2019 EDGE server
Hi Case: I have 2 Exchange 2019 EDGE servers and 3 domains. How to install and configure DKIM on 2 EDGE servers there is receiving 3 different domain? A hint would be nice :-)
Remote Server returned '550 5.1.11 RESOLVER.ADR.ExRecipNotFound; Recipient not found by Exchange Legacy encapsulated email address lookup'
Hello, We have a requirement to offboarding around 200 mailbox from exchange online to Microsoft Exchange On-premises. We have a hybrid environment and we offboarding all 200 mailboxes successfully. After offboarding, we are facing a massive issue. When…

Delegating a mailbox to another domain forest.
Hello. There are two forests. How to delegate a mailbox from domain B, to domain A ? There is a two-way trust relationship between them.
Regarding errors after migrating from Exchange Server 2013 to 2019
thank you Migrated from ExchangeServer2013 to ExchangeServer2019 I have already uninstalled 2013 because it was necessary to keep the host name the same during migration. We used a temporary Exchange Server for mailbox migration. This server is currently…


Migration from google g suite to office 365 - Error: MigrationPermanentException: The call to https://www.googleapis.com/oauth2/v4/token returned with status code Unauthorized:
Error: MigrationPermanentException -Unauthorized I have Migration from google g suite to office 365 and when i make sync it issue User status Data migrated: Migration rate: Last successful sync date: Error: MigrationPermanentException: The…