Office 2016 needs domain\ with username

[mdrabble]

Recently made quite a few changes to the network, including setting up a Hybrid Configuration for On-Premise Exchange 2013 and Office 365 and updating all clients to Office 2016

 

I have configured Active Directory to configure outlook based on SMTP address and this works great for O365 users, however on-premise users get outlook configured correctly but when prompted for credentials they need to put domain\usename even though exchange (OWA) is configured to include domain\. Meaning OWA users just type in their username and password.

 

Staff forget to add domain\ to logon details for outlook and then complain they cannot login to their emails.

 

Whats the best way around this so Outlook users do not need to keep putting domain\ first?

 

 

Cheers