Hi,

My domain is currently hosted via Google Apps.  I am piloting Office 365 E3. As such, I want to gradually move users across one at a time due to the geographically dispersed nature of my organisation.

I have created accounts on O365 and set up mail forwarders in Google Apps for each mailbox as I migrate the users, one at a time.  Google Apps is the MX for the domain, which is how I want to keep things until the migration has been completed.

What I have found is that when I create a mailbox in O365, I want Exchange to forward any mail coming to that person from inside Office 365 to go to the Google SMTP server FIRST, and for the mail to go to their Google inbox, which will then forward it to O365.

The reason I want to do this is so that if a user has had their account created on O365, but they haven't started using it, existing O365 users can e-mail them and be certain that they will receive their message, whether they are using Google Apps or O365.

Eg. I am on O365 for my domain - let's call it DOMAIN.COM.  I send an e-mail from Outlook via Office 365 to User B. User B has a mailbox in Office 365 but they haven't started using it yet.  So I want mail for USERB.DOMAIN.COM to be forwarded/relayed to the Google Apps SMTP server (as it is the registered MX for DOMAIN.COM). Google Apps' SMTP will then put the e-mail into their Google Apps inbox, which then has its own forwarding rule to send it to the DOMAIN.ONMICROSOFT.COM address.

So the end result is that both mailboxes get the message!!!  Makes sense?  Help is appreciated.

Thanks. 

Hi,

Thank you for your post. 

Here we only discuss questions and feedback for Microsoft Office client. There is not so much about Office 365 deployment/server aspects here, I would suggest you to post in the dedicated forum of Office 365 Community, where you can get more experienced responses:

http://community.office365.com/en-us/f/default.aspx

The reason why we recommend posting appropriately is you will get the most qualified pool of respondents, and other partners who read the forums regularly can either share their knowledge or learn from your interaction with us. Thank you for your understanding.

Regards,

Ethan Hua
TechNet Community Support