Unable to connect/view web pages

[tee]

Whilst my parents have been away I've been looking after their house and using their PC. For some reason when connected to broadband after a while, most pages become unavailable to view. Internet Explorer tries to connect, in fact sometimes it seems as though it isn't trying. I've tried repeated refreshes, entering in the address again and hitting enter - sometimes this works, but more often than not I'm getting the 'This page cannot be displayed' - 'Cannot find server' page. Any ideas what is going on? It seems weird that every so often I can view certain pages but for the most part I can't. Surfing th einternet is impossible! I am using BT Yahoo! broadband and Internet Explorer 6

[Pazman2k]

does a reboot solve the problem?

[tee]

Sort of. Once rebooted the pages that weren't accesible are, but after a very short while, the problem occurs again

[cjb110]

I'd guess its dns or proxies to blame.

Are you using any proxies?

Does typing the ip address directly help?

[tee]

I'd guess its dns or proxies to blame.

Are you using any proxies?

Does typing the ip address directly help?

Proxies - I don't think so? I've tried typing the URL directly and that makes no difference, not sure how (or what) to type IPs directly.......

[SPB]

What is the setup? USB modem, Ethernet router/modem, wireless????

Re: IP address. Not sure if XP has this (NT does) but you can type nslookup <sitename> in a DOS window to find out the IP address of a website, for example www.bbc.co.uk is http://212.58.224.82/. You could also just type "ping www.bbc.co.uk" in a DOS window to find the IP address (and see if you are getting out on the net at the same time). The ping will return:

"Reply from 212.58.228.154: bytes=32 time=20ms TTL=244" if all seems OK
or
"Bad IP address bbc.co.uk" (e.g.) if the DNS is screwed
or
"Pinging 58.228.154 with 32 bytes of data:
Request timed out." if the DNS is (probably) OK but the computer can't get out onto the net for some reason.

NB: Not all sites will give a ping response. I have used BBC because that definitely does!

[tee]

USB modem

[SPB]

:( Know nothing about USB, so over to somebody else.

[Choccy]

Only thing I know in this area is that it could be Zone Alarm 5.

That or I get this when I'm downloading something at the same time and it is a fast download, well it only happens if I leave it downloading for a while and then if I repeatedly open IE about ten times eventually it will find the page.

[tee]

ZonalAlarm 5 is being used on this PC (I installed it) but I have it running on mine with no problems