Hotfix rollup 2926995 is available for the .NET Framework 3.5 in Windows 8.1 or Windows Server 2012 R2

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.

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, submit a request to 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:

http://support.microsoft.com/contactus/?ws=support

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.

Prerequisites

To apply this hotfix, you must have the .NET Framework 3.5 installed.

Restart requirement

You have to restart the computer after you apply this hotfix if any affected files are being used. We recommend that you close all .NET Framework-based applications before you apply this hotfix.

Hotfix replacement information

This hotfix package does not replace a previously released hotfix package.

Issue 2

The .NET Framework 3.5 applications that are running on single core computers can freeze in GC code.

Issue 3

The w3wp.exe process crashes with an exception when System.Web.Util.ResourcePool.Finalize() is called.

Issue 4

ASP.NET applications that access additional functionality by using the application configuration settings can experience a deadlock at startup.

Issue 5

The .NET Framework 2.0 and 3.5 applications will throw a NullReferenceException exception when they use GetEnvironmentVariable if the registry key does not exist.

Issue 6

DirectorySearcher.FindOne() may throw overflow exceptions when it runs as a 32-bit process that is linked with the LARGEADDRESSAWARE compiler flag and runs on a 64-bit operating system that is configured to use 3 gigabytes (GB) of memory. Applications hosted inside IIS may see this exception when w3wp.exe is compiled as a LARGEADDRESSAWARE application.

This fix makes sure that memory addresses larger than 2 GB are handled correctly.

Issue 7

When an update is being installed, Fusion can access a state in which NGEN is called repeatedly. This causes entries in the following registry keys keep growing until the computer freezes:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\v2.0.50727\NGenService\Roots 
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Fusion\NativeImagesIndex