Users are repeatedly prompted for credentials and authentication is not successful when a downstream computer that is running ISA Server 2004 uses Integrated Windows authentication to authenticate to an upstream computer that is running ISA Server 2004

You configure a firewall chain between two or more computers that are running Microsoft Internet Security and Acceleration (ISA) Server 2004. A downstream computer that is running ISA Server 2004 uses Integrated Windows authentication to authenticate to an upstream computer that is running ISA Server 2004. The following symptoms occur:

• The authentication is not successful.
• Users are repeatedly prompted for credentials.

This behavior occurs if the following conditions are true:

• The downstream computer uses a user name or a password to authenticate to the upstream computer.
• The user name or the password contains characters other than 7-bit characters.
  
  Note English characters are 7-bit characters.

To resolve this issue, use only 7-bit characters for the user name and the password to authenticate to the upstream computer.

For additional information, see the "Web chaining rules" topic in the ISA Server 2004 Help documentation.