Mailboxes - Nothing being created for Sync'd Users

Question

hi guys,

we have sso / azure ad sync working and all has gone to plan.

we've filtered it so only specific ou's are coming over and we've tested editing/updating/deleting.

as part of this we have activated all sync'd users as per instructions and associated e3 licencing.

i'm not sure if we're being impatient however none of the users seem to have a mailbox - the email address on the right hand side when selecting a user states

primary email address:

the items you're trying to open couldn't be found.

i've attached a screengrab of that.


i'm wondering if something is wrong with the dirsync (we're getting no errors) or if it's just taking time to create the mailbox and other bits and pieces at microsoft's end?

perhaps it's something that has to be fixed on the ad side? missing attribute?

only 2 of the 100 users currently seem to have mailboxes.

kind regards,

cp

Answer 1

Hi all,

We've fed this back and asked how they would like to proceed.

Initially they would like to be Hybrid and move people over to Office 365 when they're ready, once people are over we can then flick to a standalone O365 installation potentially at a later date.

Could I ask - do you know of the best documentation for this approach, how do we tell OnSite AD to allow the mailbox to be created on the O365 side and not use the onsite?

Just a few more questions if I may.

• If we tell the AD onsite attribute that the Exchange mailbox is now to be Office 365 based, will this stop deliver to the OnPrem exchange?
• Does a hybrid installation deliver email to both Office 365 and the OnPrem Exchange or just where both the MX points and mailbox exists?

If this becomes a little over complicated and we just do a cut over/staged migration can we sync passwords with the onprem AD users? We've managed this with Windows Server Essentials I believe where we can assign an O365 user to an OnPrem AD user and I believe the credentials (password) syncs. Is this possible from Server 2015? (This is my preferred solution).

Kind regards,

CP

Answer 2

Hi Chris,

I understand you want to use Azure AD sync to manage the password from on-premises AD. However, as Allen mentioned, once the directory sync is enabled, we cannot have mailboxes for a single user on both on-premises and cloud sides. This will lead to attribute conflicts.

In this situation, we suggest you remove the license and use on-premises mailboxes. When you decide to move your users to cloud, you can consider cutover migrationor stage migration. If you want to move some mailboxes to cloud and keep the rest on your on-premises Exchange, you candeploy Hybrid.

Thanks,

Alex

Answer 3

Hi Allen,

Thank you for coming back to me so quickly.

We did a stand deployment (non hybrid) - we want to replace the onPrem exchange server with O365 Exchange.

Is this something that can be achieved? We simply wanted to manage the users/passwords from onPrem AD to simplify management.

We wanted to create the online mailboxes and migrate the data (we use Bittitan to achieve this usually) and then remove the onsite exchange at a later date.

Chris

Answer 4

Hi CP,

I’d like to further confirm the current situation. Since you have an active Exchange on-premises server, have you configured an Exchange hybrid deployment where cloud mailboxes and on-premises mailboxes can work together?

Moreover, please be aware that one same user cannot have mailbox both at on-premises side and cloud side. Therefore, please check whether the affected users already have their on-premises mailboxes. If yes, you need to decide whether they’re going to use cloud mailboxes or on-premises mailboxes. There can only be one. If the answer is cloud mailboxes, you may need to convert their on-premises mailboxes to mail users. (We can provide you with a solid answer only after you let us know the detailed environment.)

Looking forward to your updates.

Thanks,

Allen

Answer 5

I must add, there is onPrem exchange currently where these users have sync'd from. We want Office 365 to handle email going forward.

Is this not possible if the users have been sync'd from an environment where exchange exists?