Can't put the username and password in your URL anywore with IE

A security update is available that modifies the default behavior of Internet Explorer for handling user information in HTTP and in HTTPS URLs.

The following URL syntax is no longer supported in Internet Explorer or in Windows Explorer after you install the MS04-004 Cumulative Security Update for Internet Explorer (832894):

http(s)://username:password@server/resource.ext

Read the Technet article