OK, I've had iPrint working for months/years flawlessly.

NW65 SP3
iPrint client 4.05.00
Win XP SP2

I have a nw65 sp3 server behind my firewall with a private IP address and a Linux iptables rule that redirects my public ip ports 80 and 443 to the iPrint server. All has been working perfectly until today.

I can get to the iPrint web site from the outside word just fine, install the iPrint client but when I go to install a printer the PC gives the error:

ErrorCode: 10060
Error message: Winsock 10060 - Connection has timed out
Error group: WINSOCK
Error code: 10060

This is coming from a laptop via a modem connection from the outside world. Hooking up the laptop to my internal network and the problems go away.

I did a packet trace and noticed that when I click on the printer to be installed, the iPrint client immediately tries to talk to the public IP on port 631 which is IPP..

If I enable port 631 on my firewall, the printer installs just fine. I didn't have 631 enabled anywhere on my firewall(s) and haven't noticed this problem before.

Why all of the sudden am I required to have IPP port opened on my firewall? I thought that iPrint used secure http?

I'm absolutely positive I've not had to expose port 631 in the past. I port probe my firewall on a regular basis.

Thanks for any insight.