Google Data Migration Service START Button Grayed Out

So, maybe you’re like me.

You’ve got a 100 or so user’s mailboxes you need to migrate from Microsoft 365 to Google Workspace.

You’ve completed your setups; the impersonation rights are set on your global admin in M365, and, you’ve assigned full control rights over all target mailboxes.

You strike up Workspace and start the Data Migration Service, successfully authenticate, and start adding users, but it won’t let you. You’ve got a GRAY START BUTTON like this.

And it’s frustrating the hell out of you because, hey, you’re a good tech, you did your planning, etc.

Well, I found a solution.

What’s happening here is that you’ve authenticated this process under another domain and not the domain you think you’re targetting. The oAuth token isn’t being saved under the right account or domain.

For me, I was in my Google Reseller console trying to kick this off, and the damn thing was trying to target my own domain rather than the tenant’s domain.

So, kill the data migration.

Login to the admin console under a Super Admin for your domain under an incognito window and set up the Data Migration Service parameters again.

You should now be able to target a user by typing … it matches, you can press start.

There’s nothing like this in the docs, of course, but hey, I just pulled my hair out for an hour … maybe I can help save yours :)

R