Established Exchange server 2007 installation broken offsite client access after office move.

Old Office:

  Static public IP and everything worked fine. IP Scheme 192.169.5.0/24

New Office:

  New static IP from new broadband provider. IP Scheme 10.24.0.0/16. Outlook clients on the 10.24.x.x network can send and receive emails fine. From offsite OWA works fine. All offsite clients are broken.

Tearing my hair out. I have gone through all the Exchange server settings and updated any 192.168.x.x data to 10.24.x.x. Obviously I am missing something simple that relates to the IP scheme change, either public or private?

Any thoughts and direction is very welcome.

Thank you,

-Adam