Siemens HiPAth and Comodo firewall don't work together

We have a Siemens HiPath Wifi controller which has an authencation page.
When users log on to our network from a client they see an authorization page in which they’ll enter a user name and password.
When usesrs install the Comodo firewall on their client this authorization -authtication page cannot be opened.
Why?
How?
Etc?
Turn off the firewall - still the same problem
The only solution is to unistall the firewall then the authentication page shows up.