I have a Tesl$tra service with a Motorola SB5100 SURFboard modem and Telstra tells me that they do not block any ports with their service. I checked with www.canyouseeme.org and some ports are blocked (8000, 8042, 8043) while some are open (including 25 and 80). The error message for blocked ports is "Reason: Connection refused". Is that error generated by the ISP or the modem or my computer?

I also can't get to www.whirlpool.net.au which is a discussion forum for ISP consumers from my home PC but can from my work PC. Surely Telstra wouldn't block that site???

Computers & Internet - Arris - SURFboard - SB5100 SURFboard DOCSIS 2.0 Cable Modem (50120900100)