FIX: A Windows Forms application may occasionally stop responding for up to 10 minutes in the .NET Framework 1.1

Consider the following scenario:

• In the Microsoft .NET Framework 1.1, you have a Microsoft Windows Forms application that makes remote calls to a service that is running on Microsoft Internet Information Services (IIS) 6.0.
• The Windows Forms application makes remote calls to the server over a T1 connection.
• The connection uses integrated security to authenticate the users.

In this scenario, the Windows Forms application may occasionally stop responding for up to 10 minutes. Then, the Windows Forms application recovers and works correctly.

This problem occurs because the Windows Forms application waits for the call to the HttpWebRequest object to be finished. IIS 6.0 replies to the Windows Forms application's call to the HttpWebRequest object by returning a 401 Access Denied error. Then, the Windows Forms application does not try to repost by using the correct authentication data. Eventually, the problem is resolved, and network traffic returns to the regular flow.

Note After about 160 seconds of no activity, the server resets the socket. As soon as the server resets the socket, the Windows Forms application stops responding again if the Windows Forms application retries the call to the HttpWebRequest object.

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 .NET Framework 1.1 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: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

To apply this hotfix, you must have the Microsoft .NET Framework 1.1 Service Pack 1 (SP1) installed.

Restart requirement

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

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.

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: For more information about the HttpWebRequest class, visit the following Microsoft Developer Network (MSDN) Web site: