We have set up our conference rooms as resources in Exchange 2016 so people can reserve the rooms.

This has worked for years but last week, two of the rooms have stopped working.

If you use the scheduling assistant, they are greyed out for every time slot.

If you open the calendar associated with it, it gives an error saying could not be updated.

https://preview.redd.it/4reygi5io24e1.png?width=707&format=png&auto=webp&s=997ce753a0c39ff2e9816c52929b098420fc8c66

Has anyone seen this before?

I assumed it had something to do with the database having issues, since we are on the middle of migrating all mailboxes to a new database but the microsoft tech support person said that it isn't related. Because of the timing, I am not sure I believe her.

Anyone else seen this happening. Apple mail EWS hits the autodiscover pool.

Only found below blog about it. Will have to test few things in IIS maybe or hope there is an option on our LB.

https://ingogegenwarth.wordpress.com/2019/07/01/mac-exo-and-autodiscover/

Hi guys,

so we are currently moving our mailboxes to Exchange Online but aren't done yet so we're hybrid at the moment.

Our mail flow is configured so that mails are sent from our Exchange Online to our on prem Exchange from there to our gateway, which attaches the DKIM, and then out.

So our SPF includes our gateway's public IP. And for the most part that was ok. But now as we are hybrid some mails are rejected especially to other organizations using Exchange Online and the cause is that the SPF fails. The originating address is still our gateway's but the SPF also checks the Exchange Online IPs that handled the mails initially.

I have included MS's SPFs in our own and mail deliverability is working again. But why is that? Imho SPF should only check the last address of that whole chain. And when I send mails to other providers like Google, Yahoo and so on everything's working s expected. And it seems like not every organization using Exchange Online behaves that way.

What am I missing here?

anyone seen this behavior? I am migrating users from 2013 to 2019 on premise, no biggie.. make a batch for let's say 10 users (in ECP), start it... and BAM the batch has 4 users in it , not 10 lol

this is repeatable and random, fing microsoft... it's really no big deal, I believe I've seen the same behavior when moving 2013 to 2013 before too. Is it an ECP thing, avoidable with a shell command or just microsoft messing with me? :)

I haven't fully confirmed it yet, but I think if I rerun the migration for the users that went MIA it works (again randomly), no rhyme or reason I can find.

Hi,

Exchange 2019 environment - 1 DAG, 4 nodes, 4 DB copies on all nodes, 2 sites.

I’ve noticed that the replication of the mailbox database between the 2 DAG members has been failing intermittently. But not often.

Generally when the Content Index State goes into the Failed and Suspended state, I only have sync the Catalog with the following cmdlet:

Resume-MailboxDatabaseCopy -Identity DB-Name\Servername

why is this problem occurring?

Thanks

Get-MailboxDatabaseCopyStatus DB04\mbx1 | fl *


PSComputerName                          : mbx2.contoso.local
RunspaceId                              : 96d9ac83-7f8b-460b-893f-676a9f6e1f5d
PSShowComputerName                      : False
Identity                                : DB04\mbx1
Id                                      : DB04\mbx1
Name                                    : DB04\mbx1
DatabaseName                            : DB04
Status                                  : FailedAndSuspended
InstanceStartTime                       : 11/23/2024 4:53:02 AM
LastStatusTransitionTime                : 11/23/2024 4:53:02 AM
InternalStartupMessage                  : StartupFailed
InternalStartupMessageTimeUtc           : 11/23/2024 1:53:02 AM
MailboxServer                           : mbx1
ActiveDatabaseCopy                      : mbx2
ActiveCopy                              : False
ActivationPreference                    : 1
StatusRetrievedTime                     : 11/28/2024 8:15:30 AM
WorkerProcessId                         : 18152
IsLastCopyAvailabilityChecksPassed      : False
LastCopyAvailabilityChecksPassedTime    : 11/23/2024 4:53:09 AM
LastCopyAvailabilityCheckFailedID       : DatabaseCheckPassiveCopyStatusIsOkForAvailability
LastCopyAvailabilityCheckFailedErrorMsg : Database copy 'DB04' is in a Failed state on server 'mbx1'.
                                          Reason: Incremental seeding of database DB04\mbx1 encountered an
                                          error. A full reseed is required. Error: The Microsoft Exchange Replication
                                          service failed to determine if the log files in database 'DB04' are
                                          divergent from the source copy on server 'mbx2.contoso.local'. Error:
                                          Replacing the current log 'K:\Log\DB04\E0C.log' with the corresponding
                                          log from the active copy in order to continue replication between the active
                                          and passive copies failed for database copy 'DB04\mbx1' due to
                                          the following error: The process cannot access the file because it is being
                                          used by another process.
                                          . If you need to activate this database copy, you can use the
                                          Move-ActiveMailboxDatabase cmdlet with the -SkipHealthChecks parameter to
                                          forcibly activate the database copy.
IsLastCopyRedundancyChecksPassed        : False
LastCopyRedundancyChecksPassedTime      : 11/23/2024 4:53:09 AM
LastCopyRedundancyCheckFailedID         : DatabaseCheckPassiveCopyStatusIsOkForRedundancy
LastCopyRedundancyCheckFailedErrorMsg   : Passive database copy 'DB04\mbx1' has an unhealthy status
                                          'FailedAndSuspended' for duration 5.03:21:48.9410942. [SuspendComment: The
                                          database copy was automatically suspended due to failure item processing
                                          having failure item tag Reseed. At '11/23/2024 4:53:01 AM' the copy of
                                          'DB04' on this server experienced an error that requires it be
                                          reseeded. For more detail about this failure, consult the Event log on the
                                          server for other storage and "ExchangeStoreDb" events. The passive database
                                          copy has been suspended.
                                          ] [ErrorMessage: Incremental seeding of database DB04\mbx1
                                          encountered an error. A full reseed is required. Error: The Microsoft
                                          Exchange Replication service failed to determine if the log files in
                                          database 'DB04' are divergent from the source copy on server
                                          'mbx2.contoso.local'. Error: Replacing the current log
                                          'K:\Log\DB04\E0C.log' with the corresponding log from the active copy
                                          in order to continue replication between the active and passive copies
                                          failed for database copy 'DB04\mbx1' due to the following error:
                                          The process cannot access the file because it is being used by another
                                          process.
                                          ].
ActivationSuspended                     : False
ActionInitiator                         : Service
ErrorMessage                            : Incremental seeding of database DB04\mbx1 encountered an error.
                                          A full reseed is required. Error: The Microsoft Exchange Replication service
                                          failed to determine if the log files in database 'DB04' are divergent
                                          from the source copy on server 'mbx2.contoso.local'. Error: Replacing
                                          the current log 'K:\Log\DB04\E0C.log' with the corresponding log from
                                          the active copy in order to continue replication between the active and
                                          passive copies failed for database copy 'DB04\mbx1' due to the
                                          following error: The process cannot access the file because it is being used
                                          by another process.

ErrorEventId                            : 3145
ExtendedErrorInfo                       : Microsoft.Exchange.Cluster.Replay.IncSeedDivergenceCheckFailedException: The
                                          Microsoft Exchange Replication service failed to determine if the log files
                                          in database 'DB04' are divergent from the source copy on server
                                          'mbx2.contoso.local'. Error: Replacing the current log
                                          'K:\Log\DB04\E0C.log' with the corresponding log from the active copy
                                          in order to continue replication between the active and passive copies
                                          failed for database copy 'DB04\mbx1' due to the following error:
                                          The process cannot access the file because it is being used by another
                                          process. --->
                                          Microsoft.Exchange.Cluster.Replay.LastLogReplacementFailedErrorException:
                                          Replacing the current log 'K:\Log\DB04\E0C.log' with the corresponding
                                          log from the active copy in order to continue replication between the active
                                          and passive copies failed for database copy 'DB04\mbx1' due to
                                          the following error: The process cannot access the file because it is being
                                          used by another process. ---> System.IO.IOException: The process cannot
                                          access the file because it is being used by another process.
                                             at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
                                             at System.IO.File.InternalMove(String sourceFileName, String
                                          destFileName, Boolean checkHost)
                                             at Microsoft.Exchange.Cluster.Replay.LastLogReplacer.<>c__DisplayClass4_0.
                                          <ReplaceLastLog>b__0()
                                             at
                                          Microsoft.Exchange.Cluster.Replay.LastLogReplacer.HandleExceptions(Action
                                          operation)
                                             --- End of inner exception stack trace ---
                                             at Microsoft.Exchange.Cluster.Replay.LastLogReplacer.ReplaceLastLog(IRepla
                                          yConfiguration config, Int64 logGen, String oldFilePath, String newFilePath)
                                             at Microsoft.Exchange.Cluster.Replay.FailoverPerformanceTrackerBase`1.RunT
                                          imedOperation(TOpCode opCode, Action operation)
                                             at Microsoft.Exchange.Cluster.Replay.IncrementalReseeder.FCompareLogIncsee
                                          dNeeded(Action checkAbortRequested, Int64 lgenToCompare, Int64
                                          passiveEndOfLogGen, Boolean e00Exist, String endOfLogFilename, String
                                          e00Log, EseLogRecordPosition& lastLogRecInfo, Int32& endOfLogByteOffset)
                                             at Microsoft.Exchange.Cluster.Replay.IncrementalReseeder.IsIncrementalRese
                                          edRequired(Action checkAbortRequested, Int64& highestLogGenCompared,
                                          Boolean& e00IsEndOfLogStream)
                                             --- End of inner exception stack trace ---
                                             at Microsoft.Exchange.Cluster.Replay.IncrementalReseeder.IsIncrementalRese
                                          edRequired(Action checkAbortRequested, Int64& highestLogGenCompared,
                                          Boolean& e00IsEndOfLogStream)
                                             at Microsoft.Exchange.Cluster.Replay.TargetReplicaInstance.<>c__DisplayCla
                                          ss22_0.<IncrementalReseedIfNecessary>b__0()
                                             at Microsoft.Exchange.Cluster.Replay.FailoverPerformanceTrackerBase`1.RunT
                                          imedOperation(TOpCode opCode, Action operation)
                                             at Microsoft.Exchange.Cluster.Replay.TargetReplicaInstance.IncrementalRese
                                          edIfNecessary()
                                             at Microsoft.Exchange.Cluster.Replay.TargetReplicaInstance.ConfigurationCh
                                          eckerInternal()
                                             at Microsoft.Exchange.Cluster.Replay.ReplicaInstance.<ConfigurationChecker
                                          >b__31_0()
SuspendComment                          : The database copy was automatically suspended due to failure item processing
                                          having failure item tag Reseed. At '11/23/2024 4:53:01 AM' the copy of
                                          'DB04' on this server experienced an error that requires it be
                                          reseeded. For more detail about this failure, consult the Event log on the
                                          server for other storage and "ExchangeStoreDb" events. The passive database
                                          copy has been suspended.

RequiredLogsPresent                     :
SinglePageRestore                       : 0
ContentIndexState                       : NotApplicable
ContentIndexErrorMessage                :
ContentIndexErrorCode                   :
ContentIndexVersion                     :
ContentIndexCrawlVersion                :
ContentIndexBacklog                     :
ContentIndexRetryQueueSize              :
ContentIndexMailboxesToCrawl            :
ContentIndexSeedingPercent              :
ContentIndexSeedingSource               :
ContentIndexServerSource                :
SeedingSourceForDB                      : False
SeedingSourceForCI                      : False
SeedingThrottleStatus                   :
RecentServerCpuPercentage               : 14
RecentServerCpuPercentageFloat          : 14.01668
IsFileModeReplicationBeingThrottled     : False
RecentDiskReadLatencyMs                 : 0
RecentDiskReadsPerSec                   : 0
RecentDiskWriteLatencyMs                : 0
RecentDiskWritesPerSec                  : 0
CopyQueueLength                         : 4460
ReplayQueueLength                       : 98
ReplaySuspended                         : False
ResumeBlocked                           : False
ReseedBlocked                           : False
InPlaceReseedBlocked                    : False
MinimumSupportedDatabaseSchemaVersion   : 0.121
MaximumSupportedDatabaseSchemaVersion   : 0.185
RequestedDatabaseSchemaVersion          : 0.185
LatestAvailableLogTime                  : 11/23/2024 4:53:01 AM
LastCopyNotificationedLogTime           : 11/23/2024 4:53:01 AM
LastCopiedLogTime                       : 11/23/2024 4:52:28 AM
LastInspectedLogTime                    : 11/23/2024 4:52:28 AM
LastReplayedLogTime                     : 11/23/2024 4:42:39 AM
CurrentReplayLogTime                    : 11/23/2024 4:42:39 AM
LastLogGenerated                        : 8155188
LastLogCopyNotified                     : 8150731
LastLogCopied                           : 8150728
LastLogInspected                        : 8150728
LastLogReplayed                         : 8150630
LowestLogPresent                        : 0
LastLogInfoIsStale                      : False
LastLogInfoFromCopierTime               :
LastLogInfoFromClusterTime              : 11/28/2024 8:15:13 AM
LastLogInfoFromClusterGen               : 8155188
ReplicationIsInBlockMode                : False
ReplicationIsInScavengeMode             : False
ActivationDisabledAndMoveNow            : False
AutoActivationPolicy                    : Unrestricted
LogsReplayedSinceInstanceStart          : 0
LogsCopiedSinceInstanceStart            : 0
LatestFullBackupTime                    : 11/17/2024 2:06:58 AM
LatestIncrementalBackupTime             : 11/20/2024 12:07:53 PM
LatestDifferentialBackupTime            :
LatestCopyBackupTime                    :
SnapshotBackup                          : True
SnapshotLatestFullBackup                : True
SnapshotLatestIncrementalBackup         : True
SnapshotLatestDifferentialBackup        :
SnapshotLatestCopyBackup                :
LogReplayQueueIncreasing                : False
LogCopyQueueIncreasing                  : False
ReplayLagStatus                         : Enabled:False; PlayDownReason:None; ReplaySuspendReason:None; Percentage:0;
                                          Configured:00:00:00; MaxDelay:1.00:00:00; Actual:5.03:32:50
DatabaseSeedStatus                      :
OutstandingDumpsterRequests             : {}
OutgoingConnections                     :
IncomingLogCopyingNetwork               :
SeedingNetwork                          :
DiskFreeSpacePercent                    : 15
DiskFreeSpace                           : 492.4 GB (528,659,836,928 bytes)
DiskTotalSpace                          : 3.15 TB (3,463,443,378,176 bytes)
ExchangeVolumeMountPoint                :
DatabaseVolumeMountPoint                : K:\
DatabaseVolumeName                      : \\?\Volume{18a66631-7296-4ab7-a813-1ac53d19a920}\
DatabasePathIsOnMountedFolder           : False
LogVolumeMountPoint                     : K:\
LogVolumeName                           : \\?\Volume{18a66631-7296-4ab7-a813-1ac53d19a920}\
LogPathIsOnMountedFolder                : False
LastDatabaseVolumeName                  :
LastDatabaseVolumeNameTransitionTime    :
VolumeInfoError                         :
MaxLogToReplay                          : 0
IsPrimaryActiveManager                  : True
IsActiveManagerRoleUnknown              : False
MetaCacheDatabaseStatus                 : Disabled
MetaCacheDatabaseStatusMessage          : MetaCacheDatabase is Disabled.
MetaCacheDatabaseFilePath               :
MetaCacheDatabaseLastReset              :
LowestRequiredLog                       : 0
HighestRequiredLog                      : 0
IsValid                                 : True
ObjectState                             : Unchanged

Has anyone else started having issues with email being marked as spam? We have a few remaining exchange servers hosted in AWS, we manage the heck out of the IPS, SPF, DKIM, DMARC. Messages are reported as clean with every checker we run them through, domains score high in analyzers. Nothing has changed in months, but in the past week we are getting many complaints from users that emails are being tagged as spam, seems to be mainly 365 and Outlook users. Has anyone else run into this recently?

5th year going to ignite and this is the first time I got zero exchange content. They didnt even have an expert booth for EOL. I found that incredibly strange. Especially with Exchange SE coming next year. As if copilot was going to somehow replace my users needing mail servers. If someone somewhere thinks people will stop sending emails because they can have AI think for them then we are doomed as professionals and as humans. /rant

FYI, Today, we re-released the November 2024 SUs for Exchange Server. Get the details at Re-release of November 2024 Exchange Server Security Update packages | Microsoft Community Hub.

I have a hybrid environment that has a few legacy 2010 servers. We're in the process of rolling out 2019 and getting rid of the 2010. I know that the 2010 boxes are incompatible, but do I have to upgrade them to 2013 before decommissioning them? I can't seem to find a clear answer in my searching.

Is this possible? Did anyone prove it in practice? The idea is to move only the archive on-prem but leave the primary mailbox in the cloud.

Hi to all,

My work e-mail is operated on a third party company's exchange server. I am reaching it through web, thunderbird on my pc and from my android phone (added gmail as an exchange server). For a while when I receive an e-mail, it has been marked as read and since no notification is sent, I am missing some important ones. I have uninstalled my account from gmail and started using thunderbird application also on android. The issue continues.

Yesterday, I made such a test. I have sent a mail from my gmail account to my company account. I have checked from web, the mail come and marked as unread. I saw it, but never opened it. No notifications were on my phone, I never opened the thunderbird application on the phone. A few minutes later, I refreshed the web page and the mail was marked as read.

How can I find out which way does it marked as read? It is very annoying.

Our company migrated our mailboxes to Exchange Online a long time ago, and we finally upgraded our exchange 2010 hybrid on prem all the way to 2019.

We are currently using https://servername.domain.local as the virtual directory urls. I have been searching and couldnt find a solid answer related to our scenario and figured I would come here and ask.

How can we go about updating the On-Prem Administrative Center IIS Virtual Directories to https://mail.domain.com/ to administer users without breaking things?

We have AzureAD Sync and we want to be able to manage the users on the On Prem server still, but also want to utilize an SSL and Entra OIDC Modern Auth for the Exchange Administrative Center.

What I found is that it seems I only need to change the /owa and /ecp urls, but I dont know if thats correct.

Appreciate any help!

.

Scenario: Hybrid

Users have remote mailboxes enabled in Exchange on-prem and are assigned M365 licenses WITHOUT the Exchange Online service enabled but the same users show they have user mailboxes in EXO.

Shouldn't the mailboxes be non-existent?

Hello,

I will use the HVE feature in Exchange online. Here my question is; is it possible to use this feature with Outlook Client?

Thank you,

Hi,

we want to trigger mail to 5k + external users. As there is a recipients limitation of 10000 per day. My question is: Does external recipients limitation of 10000 per day? External is limited to 10k/day? or only internal recipients ?

I had a temporary issue with mail routing while making a change. I now have a bunch of emails with the eventid of DEFER. They don't appear in the normal mail queues.

Is there a way to retry these emails now I have fixed the issue?

Thanks

We had a requirement for creating a function for dormant user for MS exchange We are not sure what to include in the attributes , for example if I user is dormant for certain period of time this function should return all the attributes related to that dormant user

For example what distribution grp does the user belongs to like that

Can anyone help me

I'm working with an exchange 2019 server that was configured with an ip-less dag. I have been asked to change it to use an ip-based dag instead, but i'm not finding much info on how to make this change. I guess this would essentially be migrating from one dag to another.

I've read that you can't simply convert a dag from ip-less to ip. A new one must be created and the old one removed. But, I can't find any thorough documentation on the process.

The best I have found is a simple rundown here: https://serverfault.com/questions/716928/can-i-use-database-portability-to-convert-an-ip-less-dag-to-a-standard-dag-in-e

Can anyone provide a more detailed explanation of the process?

I have an opnsense firewall and installed the haproxy addon to configure some sites and services to pass through via host names. Everything seems to work properly for all the sites I’ve tried except Exchange. Only OWA and ECP work through the proxy. All the other virtual directories like Autodiscover and EWS have a 502 bad gateway. Even if I add specific rules to each path/subdirectory - still no love. I was hoping to use Let’s Encrypt and a wildcard cert on the HAProxy - it did work great for OWA but outlook remote anywhere or Mac/iOS (EWS) do not work… anyone know why??

Has anyone come across the below issue?

Whenever i try to open group object in ECP its is either taking forever or gives error 500.

However i am able to fetch the group related information through management shell within few seconds after i run the commands.

Issue happening only though ECP

Hi,

We have Distribution Group called Sales. This DG will consist of Staff 1, Staff 2, and Staff 3.

I want to forward the mails sent to Staff 1 user to Sales distribution group.

Also , I want to deliver mail both DG and Staff 1.

BUT For Staff 1 , I have tried Delivery Options under Mailbox Features > Mail Flow. But I am getting NDR message like below.

Remote Server returned '554 5.4.6 < #5.4.6 smtp;550 5.4.6 RESOLVER.FWD.Loop; there is a forwarding loop configured in the directory>'

What is the best practice or method?

Any help with this would be appreciated!

We are Exchange Server 2019 on-prem. I have a user that uses a Mac. She uses the native mail and calendar program. There was a problem in a sync and it regenerated 219k duplicate events on the same day.

I created a compliance search with new-ComplainceSearch and after getting those results I have 219,499 matching results according to the get.

Items : 219499
Size : 963859073
UnindexedItems : 0
UnindexedSize : 0

I run the following command:

New-ComplianceSearchAction -SearchName DeleteITMeetingJPM -Purge -PurgeType SoftDelete

I get the expected Yes, No, or All prompt and select all. It runs about five or six seconds says started and returns to the prompt but deletes nothing that I can detect. I ran it yesterday, thought maybe mailbox maintenance had to run so I waited and checked it again this morning and still no juju.

All the messages are still there. in her mailbox, and after rerunning the search I have the same number of messages.

Any idea what I may be missing?

In my workplace we have a hybrid environment with Exchange Online. Out of the 1,500 users there is one on a nearly daily basis seeing read email become unread overnight. This has been happening for the past year or so.

The user currently has a work Windows laptop with Office 365 apps installed. They also have a work iPhone with Outlook installed. Outlook on their work laptop and phone are signed into their work account. In that time they have had a change of work laptop and is now also on their third work iPhone.

The user does not have a personal phone and uses their work phone as their personal phone.

We can see from logs that such email will reach their mailbox and at some point become read. We can then see on the logs on the same night at least, that the email becomes unread again.

Curiously, twice when the user was moved to a new work phone, the problem seemed to stop for a couple of weeks, before coming back. We focussed our time on targeting the phone and thinking that swipe actions were the cause, but then hit a wall when the user showed they had no such swipe action for Outlook on their phone and reported the phone had not been switched on for a couple of days and yet the problem was still happening.

The email that becomes unread only seems to date back a couple of weeks at most from the sent date.

Is there such a setting in Outlook 365, Outlook for iOS or even on Exchange Online that could make email appear to randomly become unread? I can give more detail when requested, but a lot of investigation has happened for this.

Many thanks for any help given. We had already approached Microsoft for support, but felt their problem-solving was moving at too slow a pace.

EDIT 23/11/24:
We'd also disabled cached mode on Outlook on their work laptop for three weeks and the problem still persisted.

Hi everyone,

I'm facing an issue with some public folders on our Exchange 2016 server that I need to delete. I've tried deleting them via Outlook, the EAC, and PowerShell, but none of the methods seem to work. There are no error messages during the process.

Here’s the PowerShell command I used:

Remove-PublicFolder -Identity "\_FIRMA\Projekte.FIRMA\Angebote\KUNDE" -Recurse:$True

I get the confirmation prompt asking if I want to delete the folder, but after confirming, nothing happens. This issue occurs with multiple folders under \_FIRMA\Projekte.FIRMA.

Interestingly, even newly created folders cannot be deleted. Renaming them works fine, and I’ve already reset permissions. A server reboot and installing the latest updates have also been done, but the problem persists.

Has anyone encountered this issue before or has an idea how to resolve it?

Thanks in advance for your help!

Is there any way to check after a CU has been installed, if /PrepareAD was run before it was installed or if it is still necessary to do /PrepareAD after the CU has been installed?

Assuming the CU even installs if it has not been done...

I have two mailboxes, mailbox_a and mailbox_b. mailbox b is shared and only read by the user of the mailbox a.

The problem is that most of the mails that are directed to mailbox b are also directed to mailbox a, both in To and Cc, so that leads to having a lot of duplicate emails. How do I manage to delete mails directed to both of them ONLY on mailbox b, i want mailbox a to receive the mail as usual. ChatGPT isn't helping and neither does the internet. TIA

How do you re-install CU23 when you have already installed the exchange security updates that come afterward?

I tried installing it using gui and command prompt but neither worked (gui wouldn't let me hit next to install and command prompt seem to just skip the install). do I need to uninstall all of the exchange security updates first? that would take forever.

Trying to reinstall it based off a suggestion from Microsoft tech support. In the middle of a nightmare Exchange situation right now.

Note: Thanks for all the suggestions. Ended up manually copying files from ISO.

Hi all,

I'm hoping you good folks can help validate my line of thinking here.

Background:

We're currently still in what I would consider a traditional hybrid-exchange setup, though we do not maintain any active mailboxes in the on-prem environment and have not for quite a while now. All accounts are created in AD, added to exchange and then synced up to EOL. Most mailbox related management (alias/address changes, email deliverability settings, etc) still happen in on-prem EAC.

With that said, we can create users in AD, sync them up to EOL and fully manage all aspects of their mailbox cloud only. I've not found any limitations short of changing the users UPN, but that is a by product of the entra connect sync and not Exchange hybrid.

The only reason we aren't doing this exclusively at this point is because we have numerous LOB apps that use on-prem exchange SMTP and if the objects (users, DL's, etc) don't exist in on-prem echange NDR's are generated.

So my thought is that I can change the accepted domains in on-prem exchange to be internal relay, create the connector to deliver that domain to EOL and in theory I should no longer have to create any objects in on-prem exchange. This gets me to a point that I'm only creating accounts in AD and all other management aspects can happen exclusively cloud only, but my SMTP relay needs will still be met.

Thoughts? Does this sound reasonable? Any gotchas I'm not thinking about or considering?

anyone else having an issue with outlook for android not pulling down new emails, for me anything past 8:10 UK time today.

works on iphone and also gmail app for android