Failed to synchronize item changes in folder: TeamsMessagesData

[witt]

Hi all,

We're in the middle of migrating from On-prem to M365, and we're getting some errors in Veeam. We get the following error on 8 different mailboxes (All user mailboxes):
Processing mailbox XXX@YYY.dk failed with error: Failed to synchronize item changes in folder: TeamsMessagesData.. An internal server error occurred. The operation failed., ICS synchronization failed.

Any other with the same problem? Any suggestions to how we can backup those mailboxes?
We have a support case open with Veeam (Case #05133830), but no solution yet.

Kind regards,
Nicolai

[Natalia Lupacheva]

Hi Nicolai,

Thank you for sharing your Support case ID!
The "Internal server error" may be caused by different reasons, not sure you'll find here exactly the same case.
I would keep working with Support and check the logs.
Also, if you are unhappy with your Support case, you can always escalate it.

Thanks!

[Mike Resseler]

Hi @witt ,

I discussed this case an hour ago with our support teams. You are not the only one with this problem unfortunately, it seems to be appearing randomly with a small amount of organizations around the globe. We are discussing at this point in time a workaround and at the same time discussing with Microsoft what can cause this issue.

So for now I'm afraid there is not really a solution, but we will try to get a fix for it as soon as possible

[Regnor]

@Mike: I've also seen this error for a small set of mailboxes and been informed that you're already working on it, so all good.
But if you need any additional information or details the you can ping me; #05152256.

[Mike Resseler]

Once I have a final idea on how to solve it in the interim time, I will let you all know. It's a pain, I'm sorry for it. And I still hope it can be solved on the MSFT side, but I think we will probably have a faster (temporary) solution

[witt]

Thanks for the updates, Mike.

I hope you'll find a solution soon, permanent or temporary

Kind regards,
Nicolai

[Regnor]

There is now a private fix available. This doesn’t fix the issue, but excludes the TeamsMessagesData folder, if an error occurs, and backups the rest of the mailbox. You can get the fix from Veeam Support.

[Mike Resseler]

@Regnor is correct. The fix will also be included in a hotfix package which I expect to be online next week.