Update 5/6/2025: Please see Directory Based Edge Blocking Now Available for Public Folders & Dynamic Distribution Groups for updated information on this subject.
Note: this solution is for hybrid d...
Updated Jun 05, 2025
Version 5.0
Blog Post
4 MIN READ
Office 365 Directory Based Edge Blocking support for on-premises Mail Enabled Public Folders
Aleh,
We will investigate this scenario. Few questions:
1) Currently, when a mail is sent to on-premise distribution groups, is it being delivered to mail Public Folders (which is part of the distribution group)?
2) You are getting "completed-warnings - exported-change-not-reimported" only for mail Public Folders which are part of distribution groups & not for other mail Public Folders. Am I right?
We may need more info during the investigation. If you are interested, you can reach out to us at the following alias for further communication modernpfmigrationtoexo@service.microsoft.com. You can send the entire error message so that we will know the exact nature of the issue.
answers:
1) Currently, when a mail is sent to on-premise distribution groups, is it being delivered to mail Public Folders (which is part of the distribution group)?
- if you as sender located onpremise - yes. if mail send from o365 - No, because on o365 side DG does not contain PF as member (membership is not completely synconized).
2) You are getting “completed-warnings – exported-change-not-reimported” only for mail Public Folders which are part of distribution groups & not for other mail Public Folders. Am I right?
Not sure, for we remove this feature from production, but it possibly yes.
To sync mailPF to o365 we use now Sync-MailPublicFolders.ps1 as partial solution (sync mail addresses, not membership).
- Thanks for the replies Alah
- You will see ‘exported-change-not-reimported’ error when you have any Mail Enabled Public Folders (MEPF) as part of Distribution Lists (DL). The error is seen for each MEPF which is part of any Distribution List (DL). Impact of the error is as follows:
• As you might have already known, after we added support for syncing MEPFs to AAD, customers can enable DBEB for their organization & still receive external emails to MEPFs. Earlier, they cannot (more details can be found in this blog). Because of above bug, if a DL contains one or more MEPFs & a mail was sent to that DL from an external source, it will be received by all the recipients of the DL *except* by the MEPFs the DL contains. Note – Mails that are explicitly sent to MEPFs are delivered without any issue.
• Second impact is related to background load. As you know Azure Active Directory Connect tool does full synchronization for the first time & after that it only performs delta synchronization. Because of below error, DLs with MEPFs will be fully synchronized for every sync cycle. So, if you have large DLs with say few thousands of recipients (not just MEPFs, but all kinds of recipients included), the DL gets fully synced for every sync cycle creating load on the tool & increasing the durations for each sync.
Our suggestion is – if you don’t have any large DLs (with few thousands of recipients) which contains MEPFs, then you can ignore below error. Although, you need to take care of mails not getting delivered to MEPFs if they are sent to their parent DLs from external user. If you have large DLs that happen to have MEPF as part of them, then our suggestion would be to disable the “Exchange Mail Public Folders” option in optional features. This would remove the error from each sync cycle. But you will lose DBEB support for MEPF i.e., mails sent to MEPF won’t be received as long as DBEB is enabled.
- FYI for others - the error we are getting here ‘exported-change-not-reimported’ is a benign error. So, there is nothing that is blocking from any data of DistributionList to be synced to AAD nor there is any issue in overall sync.