I recently installed Azure AD Connect on a new server and synched all AD user accounts and security groups by mistake. I have an OU in our AD that contains all Employees with an Office 365 account and only want to sync those I set up email groups in Office 365 directly.
When it did the first sync, it included all accounts in the Users OU as expected
I changed the OU filtering in the Azure settings to only include the Employees and not the Users OU with all groups and accounts in AD that I don't want in Office 365. But it still leaves all accounts and groups from the Users OU in Office 365. And I can't manually remove them because it shows a message they are still being synched with AD on our server.
" Couldn’t delete this user because the account is synchronized with your on-premises servers. You can delete the user from your on-premises...