You install the Remote Desktop Services role on a computer that is running Windows Server 2008 R2.
You use a third-party driver on the computer. The driver subscribes state change notifications for remote desktop sessions.
The computer is running under a heavy stress. For example, multiple users frequently establish remote desktop sessions to the computer.
In this scenario, some remote desktop sessions do not completely exit on the computer. You find that there is one Csrss.exe process left in these sessions. Additionally, after some time, you cannot establish new remote desktop sessions to the computer. If you try to restart the computer to recover from the issue, the shutdown process stops responding. You have to manually turn off and then restart the computer.
The issue occurs because of a problem in the Win32k.sys driver.
If a remote desktop session exits before the session is completely initialized, the state change notification of the session is not sent to the third-party driver. In this situation, the driver can leak resources, such as a system thread, in the context of Csrss.exe because the third-party driver cannot unload. The leaked thread causes the remote desktop session not to exit completely. After the computer is running in this status for some time, the Local Session Manager (Lsm.exe) blocks new incoming connections. Additionally, these orphaned sessions also cause the shutdown process to stop responding. Therefore, you experience the issue that is described in the "Symptoms" section.
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 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, visit 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.
To apply this hotfix, you must be running Windows Server 2008 R2 that has the Remote Desktop Services role installed.
To use the hotfix in this package, you do not have to make any changes to the registry.
You may have to restart the computer after you apply this hotfix.
Hotfix replacement information
This hotfix does not replace a previously released hotfix.
The global version of this hotfix installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.
Windows Server 2008 R2 file information note
Important Windows 7 hotfixes and Windows Server 2008 R2 hotfixes are included in the same packages. However, hotfixes on the Hotfix Request page are listed under both operating systems. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows 7/Windows Server 2008 R2" on the page. Always refer to the "Applies To" section in articles to determine the actual operating system that each hotfix applies to.
The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information for Windows Server 2008 R2" section. MUM and MANIFEST files, and the associated security catalog (.cat) files, are extremely important to maintain the state of the updated components. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.
For all supported x64-based versions of Windows Server 2008 R2
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
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
Additional file information
Additional file information for Windows Server 2008 R2
Additional files for all supported x64-based versions of Windows Server 2008 R2