I deployed Sage 300 2016 Web Deployment and were able to login from client computers without "Enable Application Security" box being enabled in Database Setup Utility. However, after enabling this option, I started getting the warning message "Session could not be opened" from the client computers and defaulting back to the Sign On window.

What can I do to resolve this problem? I desperately need a solution as I will be going live with Web Deployment in two days time.