When a user connects to your server via a "multi-homed HTTP proxy" (used by large ISPs such as AOL), TCP connections come to the CommuniGate Pro Server from several different IP addresses of those proxy servers. If the Require Fixed Network Address option is enabled in the Account WebUser Preferences, user browser connections can be rejected. Disable the Require Fixed Network Address option for those users that connect via "multi-homed proxy" servers. If most of your users connect via those proxy servers, you may want to disable this setting in the Domain Account Defaults or in the All-Server Account Defaults.