Some Websites cannot be viewed
 

Hi


I am experiencing a very strange problem with a number of networked
windows PC's (mainly XP) that cannot browse particular websites.
For example: amazon.co.uk, fedex.com, ups.com

All PC's run fully patched XP SP2 with I.E. ver 6.0.2xxx.
The hardware is identical from the same supplier batch.
They also have identical software installations, DNS entries and
anti-virus software setup and share the same broadband line.
Some PC's can access the sites mentioned others display the usual I.E.
website not found page!

Here's what I've tried so far:

Cleared all offline content and content from I.E.
Installed I.E. ver 7
Installed Firefox
Tried the same sites on a number of Win98SE machines and again some can
access the sites and some cannot.
Tried a different broadband connection.

>From cmd prompt pinged the relevent sites and after a short delay (2-3


seconds) the IP address of the site resolves out and ping packets are
received back with no failure.
If the discovered IP address of the affected sites are entered direct
into the I.E. address bar the websites can be viewed.


To me this points to some sort of DNS resolution problem, perhaps the
delay is significant?

I have also checked our host files and there are fine.

Any suggestions of other things to try would be greatly appreciated as
I am fresh out of ideas.
Regards
Matt

Re: Some Websites cannot be viewed
 

All set up to use the same proxy? How are all these PCs networked?

Re: Some Websites cannot be viewed
 

Yes, they are all set to use the same proxy

They are networked on standard TCP/IP Windows Workgroup.
We have 2 machine which are on the same network, in the same office and 1 can access ups.com, fedex.com and 1 machine cant

Re: Some Websites cannot be viewed
 

So is there just one router on the network, and does the router allocate the PC's IP addresses, or are those IP's fixed? In the IE and the network settings for the cards, have you entered any fixed IP ranges for DNS servers, gateways and the like, and do these all match up?

Re: Some Websites cannot be viewed
 

Every PC has a fixed IP
All DNS Settings and gateways all match on every machine

Re: Some Websites cannot be viewed
 

I'd be focusing on the router / proxy then that you are using, and whether that is in fact handling things as it should. Try resetting it, and refreshing / releasing any IP leases. If you have given fixed IPs are those reserved / excluded from allocation in the router / proxy / DNS lists?

Re: Some Websites cannot be viewed
 

Maybe a hosts file, or adblocking software could be causing it ?

Re: Some Websites cannot be viewed
 

We have bypassed the proxy server and gone straight to the router, and also tried a different router and broadband line

the host files are ok, and there are no adblocking software installed on any machine

Re: Some Websites cannot be viewed
 

can anyone help?

Re: Some Websites cannot be viewed
 

Are all the problem sites secure sites? I'm guessing ups, fedex & amazon are?

Is the mtu the same on all machines? Have a look here...

Sorry, you're going through a router! What's the router's MTU set at as well?