So 10 months later I've setup a new system (a thin client to run the weather station -- I'll publish a lot more about it once I get this working) and I'm dead in the water again in almost the exactly same place...
Brand new XP install, no anti-virus, only the windows firewall active (yes, a risk, but I want to keep the debug of this problem as simple as possible). Only WL 5.8.0 installed and the SI lab drivers to map the USB port to a pseudo-serial connection.
The VP2 and WeatherLink are communicating just fine -- I can see the station's data in the WL app, and it updates in real time. I can browse the internet just fine -- the network is up and running.
No other software whatsoever (well, Adobe reader so I could read some documentation).
In other words an absolutely clean system.
I have quadruple checked my weather underground station name and password. When I start the real time updates it report success but nothing updates on the weather underground web page.
When I open the weather underground settings and click "test" it report success too -- but nothing updates on the web page.
For the record:
XP Pro, SP3
Intel D945GCLF motherboardSeagate 160gb drive
That's it, not even a CD/DVD drive.
Does anyone have any insight as to what's happening, or should I say isn't happening?
Roak