We plan on migrating 70 users from on premise Exchange to Office 365. The on premise will stay on the domain for a few weeks after the migration. Below are the steps in general I plan to do. I have a few questions.
Is there a way to automate the removing of the old profile and adding the new one that will point to Office 365? I'm trying to void logging into each desktop if possible.
Is there anything else I need to do to make sure Outlook doesn't try to connect to the old Exchange server? It has to stay online for while after the migration...
Start the migration in roll ups from On Premise to Office 365 (while that's running start the below steps)
Schedule the last roll up to be done Sat evening
Then change public DNS to point to Office 365. Then change the public autodiscover records and private autodiscover records to point to Office 365 for their domain.
Log into each desktop, delete old profile, add a new one with a different name. (see about a method that will automate this)
Configure profile to access Office 365 account (assuming there isn't an automated way)
Set Outlook instances that support selective offline cache to only sync back 3 months. We can later change if desired.
Once you migrate the mailboxes and re-home autodiscover records to Office 365, Outlook will properly configure things and your users will be able to connect to the Office 365 mailboxes without any changes to Outlook (Usually. Sometimes you have to repair the profile or recreate it). They will be prompted for credentials the first time and they just need to put in their Office 365 Creds. If you're using a Hybrid setup with ADFS, their username and password won't change. If you're using ADConnect with password sync, they'll have to use their email address as their username, and that's about the only difference. In a hybrid environment, everything that Outlook needs to find and connect to the mailbox is synced to the cloud, so as long as Autodiscover is already configured prior to migration and all outlook clients are using it, you don't need to do much of anything for Outlook to keep working after migration.