I have enabled remote access to the web interface but I can’t connect

For IPCOP 1.4.x: Many ISPs block port 445 due to a known Windows flaw. Most ISPs will deny blocking any port but if you question them on port 445, they will admit it. Trying to get your ISP to open this port for you will get you very little progress. Instead, change your SSL port on IPCOP.

For IPCOP 2.x: This no longer applies as the default https port was moved off of 445 to port 8443 (not port 81 no longer redirects).