What model is it and I will tell you if there is any form of update available.
Afaik though, there isnt any form of EPG update service for ex-ITV Digital/OnDigital boxes, because its summit to do with Canal+ actually own the boxes, although they arranged a deal with ITV when they went bust whereby people could keep the boxes (it would have cost millions to collect them all), and they also own and developed all the software used by ITV, and as ITV no longer pay any development costs, they no longer develop for it.
You have to remember with ITV Digital boxes that they were subsidised, so they were (and still are) quite basic and locked down. The CAM on them is pathetic to tell the truth.
Mark, no need for him to try the cable forums for a DTT box?? I dun understand that lol.