Users receive a "The parameter is incorrect" error when they try to access a Web site through ISA Server 2004

Assume that you have configured Microsoft Internet Security and Acceleration (ISA) Server 2004 to route all traffic to an upstream proxy server. When a user tries to access a Web site through ISA Server 2004, that user receives the following error message:

This problem occurs if all the following conditions are true:

• ISA Server has a Web chaining rule that is configured to route all traffic to an upstream proxy server.
  
  Note In this scenario, this proxy server might be a virus scanner proxy server, a content-filtering proxy server, or some other similar type of proxy server.
• The upstream proxy server is running on the same computer that is running ISA Server 2004.
• ISA Server is running on a stand-alone server and not on a server that is a member of a domain.

Service pack information

To resolve this problem, install ISA Server 2004 Service Pack 1 (SP1). For additional information about how to obtain ISA Server 2004 SP1, visit the following Microsoft Web site:

To work around this problem, install the upstream proxy server on a different computer, and then configure ISA Server 2004 to route traffic to that upstream proxy server computer. For additional information about how to configure Web chaining rules, see the following topics in the ISA Server 2004 Help documentation:

• "Web chaining rules"
• "Create a Web chaining rule"
• "Configure how Web chaining rules retrieve requests"

Note Depending on your environment, you can also work around this problem by adding the ISA Server computer to a domain.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

For more information, click the following article number to view the article in the Microsoft Knowledge Base: