Internet Explorer 8 won’t access Amazon.com

A strange and challenging problem with IE 8 (and IE 7 before upgrading). I’m unable to access www.amazon.com. The error page reads “Internet Explorer cannot display the webpage” with a linked button offer to diagnose connection problems. Under the security options of IE 8, www.Amazon.com is not listed within “restricted sites” in fact, it’s in the trusted site catagory. But I am able to access amazon.com from other browsers such as Chrome and FireFox. Any suggestions?