IMAP migration incremental sync not working

Question

Hello,

I've created an IMAP migration plan to Office 365 from our current email server. I've tested the plan using only one user. The creation of the migration endpoint, of the migration batch and the initial synchronization worked just fine. 

After the weekend I checked the status of the migration batch and saw that the incremental synchronization didn't occurred over the weekend. The status of the migration batch is Synced and in the statistics report I can see that the last synced time is actually before the initial sync time. This is strange...

I checked my inbox in Outlook Web Access and the emails are not there. 

Is there any way to setup the incremental synchronization for an IMAP migration? 

Thank you in advance

Nick

Answer 1

Hi Nick,

Yeah, you are right. However, I checked the incident of EX42979 and found it was restored at Saturday, February 20, 2016 08:20:00 AM. So it might not be the root cause.

Let’s continue to troubleshoot this issue. From the second screenshot, I notice that Office 365 is not able to access your account using the credentials that you provided. Please make sure that the other user didn’t change this account’s password, and double check the user name and password in the CSV file.

Additionally, to narrow down the root cause, I suggest you create a new CSV file with a new test account and check if the issue still exists.

Best Regards,

Toby

Answer 2

Hello Toby,

In the csv file I have to use a migration administrator account. The account used Friday is the same today. Absolutely nothing changed. Friday worked today is not working.

I tested the migration batch using a csv file created with the user's moilbox credentials. Is working.

Thank you very much for your help, I'll try to find the problem when creating csv file for the migration admin. I think the account username could be the problem.

Best regards,

Nick

Answer 3

hello toby,

i've started investigating further the problem and found that on friday in the evening a problem occurred in the functionality of exchange online. the incident is ex42979 and is affecting migrations.

i deleted the migration batch, the migration endpoint and the user mailbox in office 365. i created all of them again using for the migration batch the csv file used successfully on friday morning. the 2 servers are synchronizing all the emails until the first synchronization occurred (friday morning). all the emails i received after that moment are not synchronized. in the statistics area the last synced time is friday morning.




thank you very much

nick

Answer 4

Hi Nick,

To protect your privacy, I have masked the email address in the screenshot you uploaded.

Generally, if we don’t delete the batch or manually stop it from syncing to Office 365, it will keep syncing. And after initial synchronization is complete for the migration batch, mailboxes in the IMAP messaging system and the corresponding Exchange Online mailboxes are synchronized every 24 hours. This means that any new messages sent to the mailboxes on the IMAP server are copied to the corresponding Exchange Online mailboxes. By default, incremental synchronization is performed on 10 mailboxes at a time until all mailboxes in the migration batch are synchronized. Incremental synchronization continues until the administrator stops or deletes the migration batch.

Regarding this issue, I wonder if you deleted the CSV file. If not, I suggest you delete the original batch, then create a new one and check if the issue will go away.

Tips: It just syncs emails which didn’t sync to Office 365. The old emails will not sync to Office 365 again.

If the issue still exists, please upload two screenshots about details of the batch and the endpoint you created, so we can try to reproduce it.

Best Regards,

Toby