FIX: Error message when you try to browse the root folder of a Web application that is built on the .NET Framework 2.0: "Object reference not set to an instance of an object"

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When you try to browse the root folder of a Web application that is built on the Microsoft .NET Framework 2.0, you may receive the following error message:
Object reference not set to an instance of an object
This problem may occur when the following conditions are true:
  • You use Microsoft ASP.NET wildcard application mapping.
  • The default page for the root folder of the application inherits from a custom Page type.
You may also notice that URL rewriters that use directories as friendly URLs do not function correctly.
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 Microsoft .NET Framework 2.0 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.

Restart information

You must restart your computer after you apply this hotfix.


The following list contains prerequisites for the hotfix:
  • Microsoft .NET Framework 2.0

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.
File nameFile versionFile sizeDateTimePlatform
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:
824684 Description of the standard terminology that is used to describe Microsoft software updates
For more information about how to install wildcard application mappings in Microsoft Internet Information Services (IIS) 6.0, visit the following Microsoft Web site:

Article ID: 911300 - Last Review: 01/17/2015 12:38:04 - Revision: 2.0

  • Microsoft .NET Framework 2.0
  • kbnosurvey kbarchive kbhotfixserver kbfix kbqfe KB911300