HOTFIX: You cannot open a Web page by using IE7 if the URL of the Web page contains non-ASCII characters
You cannot open a Web page by using Windows Internet Explorer 7. This problem occurs if the following conditions are true:
• In the Internet Options dialog box, the Send UTF-8 URLs check box is cleared on the Advanced tab.
• The URL of the Web page contains non-ASCII characters.
• The Web page contains frame contents.
• After the HTTP response is received, each element of the frame is redirected.
http://support.microsoft.com/default.aspx/kb/935729