I can't comment on your doubts about a settting in 7 being the culprit, but I can tell you for certain that it would appear I am the only person with this problem. I have searched far and wide on the net and there is not one single posting that mirrors my problem.
The pdf link model appears to be different to what I have, and I don't know anything about telnet, so I don't know if this would help me as my only objective in the router configuration is to open ports.
Thank you for your reply, though, Tripredacus.
To clarify, telnet is the "real thing", just like command line is often the simple, plain way, in which you can usually do more than in a GUI.
Given that you have issues in Windows 7 with three different browsers I doubt that it is a specific browser issue and it is more likely that it is a "systemwide" and "OS specific" kind of issue (as an example a particular antivirus or antimalware or the built-in firewall, or some other OS program or setting).
Since it would be foolish to attempt installing the IE8 (that is working on your XP) to the Windows 7, what you can try is to use a PORTABLE version of a browser and test this portable version under the two OS.
Specifically I would suggest you to ty the good ol' Opera@USB version 1217:
as it is small and simple enough and should be able to work on both systems just fine, without altering anything of your installed browsers.
Even simpler (as a test) I would also try the OB1 browser, since it is the most basic one you can find, if you see it not working (on the XP OS) it should mean that that Zixel thingy uses one of the non-plain-html technologies:
Edited by jaclaz, 13 April 2015 - 12:18 PM.