found a fix here http://support.microsoft.com/?kbid=315054
You Cannot Disable an Automatic Configuration Script in Internet Explorer
This article applies to
This article was previously published under Q315054
When you try to browse the Internet with Internet Explorer, you may receive the following error message:
Page Cannot Be Displayed
Also, if you clear the Use Automatic Configuration Script check box in the Automatic Configuration section of the Local Area Network (LAN) settings dialog box in Internet Explorer properties and then return to the dialog box, the change is not retained and the checkbox is again enabled.
Software that maintains the Internet Explorer proxy settings may be installed. This issue has been reported to occur after you uninstall the @Home Internet software.
To resolve this issue:
Click Start, click Control Panel, and then start the Add or Remove Programs tool.
Remove any unnecessary Internet software.
Test Internet Explorer to determine whether the issue is resolved.
If the issue is not resolved, quit all instances of Internet Explorer.
Click Start, click Run, type regsvr32 /u ahiehelp.dll, and then click OK. The following message indicates that the command was completed successfully:
DllRegisterServer in ahiehelp.dll succeeded.
You can then remove the automatic proxy settings in Internet Explorer and restore your ability to browse.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article. The third-party products that are discussed in this article are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.