When you try to re-authenticate the OWA client on the forms-based authentication page, you may receive an "Unknown Request" error message in ISA Server 2004 (900249)


The information in this article applies to:

  • Microsoft Internet Security and Acceleration Server 2004 Service Pack 1, when used with:
    • Microsoft Internet Security and Acceleration Server 2004, Standard Edition

SYMPTOMS

You publish a Microsoft Exchange Server 2003 Outlook Web Access (OWA) server that uses forms-based authentication in Microsoft Internet Security and Acceleration (ISA) Server 2004. When you try to re-authenticate the OWA client on the forms-based authentication page, you may receive the following error message:
Unknown Request

CAUSE

This problem occurs if the following conditions are true:
  • You configure a Web listener in ISA Server 2004 to use OWA forms-based authentication.
  • The forms-based authentication cookie has expired on the OWA client.
When you try to re-authenticate the OWA client on the forms-based authentication page, the error message occurs. However, after the OWA client updates the Web page, the authentication process is successful.

Note See the "More Information" section for information about how to enable OWA forms-based authentication in ISA Server 2004 and how to specify a time-out value for a forms-based authentication cookie.

RESOLUTION

Service pack information

To resolve this problem, obtain the latest service pack for Internet Security and Acceleration Server 2004. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

891024 How to obtain the latest ISA Server 2004 service pack

Hotfix Information

A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Only apply it to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next ISA Server 2004, Standard Edition service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/contactus/?ws=support

Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

Prerequisites

ISA Server 2004 Service Pack 1.

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

891024 How to obtain the latest ISA Server 2004 service pack

Restart requirement

You do not have to restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File information

The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.
   Date         Time   Version       Size     File name
   ---------------------------------------------------------------
   29-May-2005  22:03  4.0.2163.270  143,360  Cookieauthfilter.dll

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. This problem was first corrected in Internet Security and Acceleration Server 2004 Service Pack 2.

MORE INFORMATION

To enable OWA forms-based authentication for a Web publishing rule in ISA Server 2004, follow these steps:
  1. Use an account that has administrative credentials to log on to the computer that is running ISA Server 2004.
  2. Click Start, point to Programs, point to Microsoft ISA Server, and then click ISA Server Management.
  3. In the left pane, expand the server name, and then click Firewall Policy.
  4. In the right pane, right-click the Web publishing rule that you want to configure, and then click Properties.
  5. In the Web publishing rule properties dialog box, click the Listener tab.
  6. In the This rule applies to requests received on the following listener list, click the listener, and then click Properties.
  7. In the listener properties dialog box, click the Preferences tab, and then click Authentication.
  8. Click to select the OWA Forms-Based check box.
  9. Click OK three times.
To configure a time-out value for an OWA forms-based authentication cookie in ISA Server 2004, follow these steps:
  1. Click Start, point to Programs, point to Microsoft ISA Server, and then click ISA Server Management.
  2. In the left pane, expand the ISA Server computer name, and then click Firewall Policy.
  3. In the right pane, right-click the Web publishing rule that you want to configure, and then click Properties.
  4. In the Web publishing rule properties dialog box, click the Listener tab.
  5. In the listener properties dialog box, click the Preferences tab, and then click Authentication.
  6. Click Configure next to Configure OWA forms-based authentication.
  7. Set the time-out value that you want next to Client on public machines.
  8. Click OK four times.
Modification Type:MinorLast Reviewed:10/12/2006
Keywords:kbfix kbbug kbHotfixServer KB900249 kbAudITPRO
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