KB Article: http://support.microsoft.com/kb/834489
This article is intended to notify Web site administrators and IT professionals about the behavior of Internet Explorer when user information is included in a Web site address (HTTP or HTTPS URL).
By default, versions of Windows Internet Explorer that were released starting with the release of security update 832894 do not support handling user names and passwords in HTTP and HTTP with Secure Sockets Layer (SSL) or HTTPS URLs. The following URL syntax is not supported in Internet Explorer or in Windows Explorer:
This article is intended to notify you of this default behavior of Internet Explorer. If you include user information in HTTP or HTTPS URLs, we recommend that you explore the workarounds that are described in this article. For more information about the 832894 security update, visit the following Microsoft Web site: