You might try removing the texissct.dll file, and that should be automatically recreated. It looks as if you are communicating with ls.thunderstone.com correctly, unless the firewall is changing the data.
Could you please help me too? I'm having the some kind of problems: I get the same error msgs in "texis.exe" and "gw.exe" as 1-cad, and I get the same msg than 8-haim while executing "geturl http://ls.thundestone.com". But I think I'm still some steps behind the answers above, because the file "texissct.dll" is not found on my server... As I install, it has a series of DOS screens showing up fast, and they look like error messages (I cannot read them, too speedy...), and the final installation screen has no other options than "Exit" button.
Thanks in advance,
jorgemc