You Receive a "Page Cannot Be Displayed" Error Message When You Post to a Site That Requires Authentication

Internet Explorer may not post data from a POST request and you may receive a "Page cannot be displayed" error message. This problem may occur if the following conditions exist:

• You perform the POST request on a new connection with a target page that requires authentication.
• The server immediately replies to the POST request with a "401 Access Denied" response and closes the connection.

The server closes the connection without reading the whole request body, and the server resets the connection when it receives frames that involve the entity body for the POST request. Because the connection is reset, Internet Explorer (Wininet.dll) cannot read the "401 Access Denied" response and process it.

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language. The English version of this fix has the file attributes (or later) 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.

You might be able to work around this problem by making sure to use the POST request on an already authenticated connection. You can do this, for example, by sending a GET request before you send the POST request.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

The hotfix that this article describes implements a code change in Wininet.dll to:

• Detect the RESET condition on a POST request.
• Save the data that is to be posted.
• Retry the POST request with the content length set to 0. This prevents the reset from occurring and permits the authentication process to complete.
• Retry the original POST request.