Migration from On-Premises Exchange to O365 and Shared Mailboxes

[Mark.S]

Currently we have several shared mailboxes which are used in our Hornbill environment, which reside as shared mailboxes in our On-Premises Exchange. We are in the process of migrating to O365, and want to make the switch over of these as seamless as possible.

Our current setup has outbound emails routing through our external email security and archiving solution, which we intend to keep this way. Inbound emails are currently done through IMAP4 connections to On-Premises Exchange, using basic authentication.

• ExternalDomain.com
  • Outbound routed via SMTP host at external email security and archiving solution
• SharedMailbox1@ExternalDomain.com
  • On-Premises Shared Mailbox, connected to via IMAP4 with basic auth
• SharedMailbox2@ExternalDomain.com
  • On-Premises Shared Mailbox, connected to via IMAP4 with basic auth
• SharedMailbox3@ExternalDomain.com
  • On-Premises Shared Mailbox, connected to via IMAP4 with basic auth

 

What would be the recommended way to configure for migrating to O365, keeping the Outbound being routed through the SMTP host currently in use. Additionally, how would we go about access the shared mailboxes as shared mailboxes within O365?

[Martyn Houghton]

@Mark.S

As the authentication for inbound and outbound are segregated you should be able to setup OAuth keysafe objects for each of your mailboxes to use with the IMAP connections to the mailboxes once they are migrated to Office365.

 Example IMAP setup we are using below.

Cheers

Martyn