I have also not been able to access the TV portal for two days, and I don't think that is going to change anytime soon. You will note that the error message quoted is an application error. It is not a connection failure; if it was there would be some interval of time where it would try to connect, whereafter it would time out. It occurs immediately one tries to access TV portal. Therefore, it must be Humax themselves who are denying entry, based on the hardware and software version. It is my opinion that it's a planned obsolescence move, with the cynical aim of making you spend more money on a new PVR.
I mainly use the portal for BBC iPlayer. Only a few months ago, the BBC removed the radio component of this, putting it on iPlayer Radio application, which so far appears to be unavailable on my HD-FOX T2. From September, I understand (if that is correct) that the remainder of that particular version of iPlayer will be unavailable. Humax appear to have preempted this be effectively removing the portal, unless you have at least version 1.03.12 of the firmware, which is not available for HD-FOX T2.
My solution for the moment is to use my laptop and connect it to the telly via a HDMI cable. Why should I spend several hundred pounds on a new PVR?