Internet Explorer, Proxy settings correct, internet access suddenly stopped

maybe somehow a problem with you dns?

do the DNS settings of the machine where it works differ from a machine where it doesnt work?

check this using ipconfig /all command

Hi,

Try resetting your Internet Explorer settings to their default settings.
http://www.malwarehelp.org/how-to-reset-internet-explorer-6-to.html

Also, are you able to receive e-mail or anything? Has there been any other changes to your network since this started happening?

Cheers,
Perry

Yes, everything else works, only the internet, intranet is ok, we have a couple hundred machines, they all work fine but this one and the one that had this issue last week which I had to reimage.

Are there any errors in event viewer? can you run SFC /Scannow on the machine?

I've got to ask, why are you still using IE6?  

yes
try firefox better security

We are still using IE 6, becasue some of the web interface software that we use, the developers don't want to support any of the later versions.

IE 8 has a compatibility mode - push a button, and it "goes back to IE 6".  It's new, so there's not a lot of feedback about it, but from a surface view, it seems to work the way it's intended to.

I don't mean to derail this question though.  

Go to the network connections and right click on your LAN / Ethernet connection.  Click properties, select TCP/IP from that list (usually at the bottom), and tell us what those are set to.  You may need to double click.

It is set to dhcp, it seems as if the proxy settings componet of IE 6 is being ignored. Intranet ok, click on an external internet site,  you immediately get the page cannot be displayed error, like its not even trying to access the proxysvr

I guess others are having the same issue,
http://wiki.answers.com/Q/Your_microsoft_internet_explorer_is_not_working_suddenly._The_proxy_settings_are_correct..._It_suddenly_happened...Anybody_has_a_solution