You cannot be successfully authenticated when you try to gain access to a page on a computer that is running Microsoft Internet Information Server (IIS) that is configured to use NTLM security if your user name or password contains an extended character (for example, an N with a tilde character above it).
You can log on to the Microsoft Windows NT-based domain and gain access to network resources, but when you try to gain access to a page on the IIS server from Internet Explorer, you are prompted three times for your credentials, and then you receive HTTP error 401.
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