Ok, so I can - but only using BT HH 6 but I wondered if for some strange reason BT blocked it for other routers as I can't anyone else's router to open it.
Port 64100 is an embedded port in my gate entry system and I NEED it open. The HH6 is a VDSL solution but as I have cables under the floor I wanted to go to a modem plus router solution. So, I have an old openreach modem with an ethernet cable runnng to a D-Link router. Can open all ports but NOT 64100. To test another, I removed the modem/router set-up and replaced with an Asus VDSL and that wouldnt open it either. I then went back to the HH6 and there it was, open again.
Both Asus and D-Link 1st line support are stuck. I think to resolve this might be impossible but it is bugging me as to why this is happening? Surely both the Asus and the D-Link can't be faulty!
Thanks to ant senior networking guru out there that can help!
No blocking of port 64100, using a DrayTek Vigor 130 and FritzBox in router mode. See image. Something is going on with your hardware from the looks of things. Have you tried a factory reset of the routers and then doing your port forwarding again to see what happens?
As you say the hub 6 shows the port open it must be the other hardware not behaving.