Some stability issues occur when you run an application that uses the DirectWrite API

You experience stability issues when you run an application that uses the DirectWrite API in Windows 7 or Windows Server 2008 R2. Because Windows Presentation Foundation (WPF)4 uses DirectWrite APIs in Windows7, any WPF4-based application is susceptible to these issues. For example, you may experience one or more of the following issues when you use Microsoft Visual Studio 2010.

Issue 1

The Visual Studio IDE crashes when you open a font drop-down list in the XAML UI designer.

Issue 2

A process preforms some operations that change the time stamps of installed font files. Then, when you start Visual Studio 2010, the Visual Studio IDE crashes.

Cause of issue 1

This issue occurs because the font cache in the DWrite API caches the 32 most recently used font face objects when Visual Studio is enumerating fonts. Each font face object maps a font file into memory. When the font files are very large, they consume a large amount of memory. This causes an out-of-memory error, which causes the Visual Studio IDE to crash.

Cause of issue 2

This issue occurs because the fonts on the disk and the font cache are not synchronized. This causes a DirectWrite API method to report a DWRITE_E_FILENOTFOUND error when it detects a change in the font file time stamp. Eventually, this error causes the WPF component and the Visual Studio IDE to crash.

Hotfix information

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 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.

Prerequisites

There are no prerequisites to install this hotfix.

Restart requirement

You do not have to restart the computer after you apply the hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

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 item in Control Panel.

For all supported x86-based versions of Windows 7

For all supported x64-based versions of Windows 7 and of Windows Server 2008 R2

For all supported IA-64-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: