Memory usage of AD FS federation server keeps increasing when many users log on a web application in Windows Server 2012

Applies to: Windows Server 2012 DatacenterWindows Server 2012 DatacenterWindows Server 2012 Standard More


Assume that many users log on a web application by using an Active Directory Federation Services (AD FS) federation server that is running Windows Server 2012. In this situation, the memory usage of the AD FS federation server keeps increasing, and you cannot log on to the federation server.


This issue occurs because AD FS federation server uses the WindowsUserNameSecurityTokenHandler class that creates token handles. However, the class does not free the handles correctly when many users log on to the web application.

How to obtain this hotfix

To resolve this issue, we have released a hotfix for Windows Server 2012.

Hotfix for Windows Server 2012

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that described in this article. Apply this hotfix only to systems that are experiencing the problem described in this article. 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, go to the following Microsoft website: 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.

Hotfix detail information

There are no prerequisites for installing this hotfix.
Registry information
To use the hotfix in this package, you do not have to make any changes to the registry.
Restart requirement
You may have to restart the computer after you apply this hotfix.
Hotfix replacement information
This hotfix does not replace a previously released hotfix.


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

More Information

For more information about software update terminology, 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