Hi Broni,
Progress report.
Firstly where in the HijackThis log do you see Norton? I could only find Symantec, same company but this is AV not firewall.
Secondly reinstalling the DLink software produced the same error messages, plus what I was hoping would not happen, unable to reestablish the wireless connection. It would connect then moments later lose the connection and I would have to repeat the process.
The help person at the ISP suggested that the modem might be dying, but had no way of establishing if that was the case.
The computer is going to be moved to another room where it will almost have line of sight for the wireless connection, plus a much shorter distance, but the ISP person's suggestion raises a question. How do you establish if a modem is dying? And are there sites that rate modems? I suppose Google could answer the second question quicker than you would be able to reply to this post, but the first question, I would not know where to start.