Unable to send email for exchange 2010 users after exchange 2013 installation.
Only users created in exchange 2013 after the installation of Exchange 2013 can send emails out.
Everyone can receive.
I've tried to add the new Exchange 2013 (all roles installed including cas) to the send connector. I've tried to switch server in the nat rule in the firewall. I've tried smarthost.
Users that have their mailbox in Exchange 2010 are no longer able to send emails
Thanks for your help