Some sites don't respond if using a newer version of flash or if the browser plugins aren't updated. I couldn't get youtube for a day or so until I sussed out that shockwave flash was a different version (and the browser plugin was affected).

Further thoughts! On Tuesday we had a sudden T-storm that actually blew a hole in my router and took the power out for a while. Now I suspect that it's blown a similar hole in that PC somewhere. My other PC obviously escaped.

In reply to a post by Andrew_W:

Further thoughts! On Tuesday we had a sudden T-storm that actually blew a hole in my router and took the power out for a while. Now I suspect that it's blown a similar hole in that PC somewhere. My other PC obviously escaped.

We had power surge some time ago, it blew the power supply in the PC and ALL the ethernet ports in the Zyxel router. You can connect to the router, but it is so slow that virtually nothing gets through.
As it happens the router works perfectly via WiFi connections !
So if anyone wants Zyxel 2602 ADSL2+, VoIP, lifeline, wireless only router, give me a shout....
Regards,
Martin

Thanks Martin for your comments!!

I've come to the conclusion that it's time to build another PC, not done it for a while and this one is a bit old

Check you haven't got "automatically detect settings" in your proxy settings.

Thanks but I haven't!

Further to my comments earlier, I had forgotten that the PC I am having problems with has another HD fitted but not connected. When I connected it back up I found that it has Win 98 on it!!!

However, 98 would run and when I connected online via the exact same motherboard/network setup as XP uses it ran OK with web pages opening instantly.

So, what does that tell me, XP is corrupted somewhere? I ran sfc /scannow with the original XP CD but no change. Next to an XP reload, is there anywhere else I could look or try an XP repair from the CD?

at a guess its a default gateway issue,
is the machine running dhcp?
what does ipconfig (from a command prompt) show?

Thanks for your reply.

Yes, DHCP enabled. ipconfig flashed up on the screen and vanished, it took several attempts to capture it to read it! As follows:

Connection specific DNS suffix edimax.com
IP Address 192.168.2.2
Subnet mask 255.255.255.0
Default gateway 192.168.2.1

My other PC that works OK is the same except the IP address ends in 3

those numbers all look right,
does the machine have (or previously had) any other networking devices,
for instance wifi or firewire?

the only other thing I can think is the network card goes to sleep, (maybe in a power setting option)