Can't login to account from one particular machine

[JLC]

Just that really. I have a TV account, and can log into if from my Linux laptop. However my other Linux machine refuses to login (just waits ages and the grumbles "can't contact server").

Trying to assign that machine to an account just fails (no error message).

Here's the killer punch. That machines status can be seen from my laptop. So something is talking.

Contacted TV support  week ago, and have been ignored.