Have a look HERE
For a while my Internet Explorer 7 would take a long time to load the the Yahoo home page and when I checked the LAN settings in Internet Connection properties, I found the the automatic configuration script had been ticked with the following address http://localhost:9100/proxy.pac and I cannot remember at any point making this as a setting.
Even when I untick the box and remove the URL address, I cannot confirm this permanently as the "apply" button is greyed out and every time I re-launch, I have the same problem.
I have tried re-booting under safety mode with full admin rights to make the change, but I still cannot make the change to "automatically detect of settings" configuration.
Besides the long loading time, Is this a security problem?
My only solution so far is to use Mozilla as this does not depend on the internet options found in Control Panel (as does Safari or Google Chrome). This is not a problem except when I need to use the Microsoft Updates site, Mozilla is not accepted!