The translucent layers intermittently turn gray when you browse a Web page that contains translucent layers by using Internet Explorer 7

You develop a Web page that contains translucent layers. In the Web page, you use the Filter property to adjust the opacity of the translucent layers. When you browse this Web page by using Internet Explorer 7, the translucent layers intermittently turn gray.

This problem occurs because of a race condition in Internet Explorer. This race condition occurs when two threads concurrently call the SelectObject function on the Windows GDI HBITMAP handle.

Windows Vista service pack information

To resolve this problem, obtain the latest service pack for Windows Vista. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

Hotfix information for Windows Vista

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. 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

To install the hotfix, you must have Internet Explorer 7 installed.

Restart requirement

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

Hotfix replacement information

This hotfix does not replace any other previously released hotfixes.

Registry information

Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

To use this hotfix, follow these steps:

1. Click Start, type regedit in the Start Search box, and then press ENTER.
2. Locate the following registry subkey, and then click it:
   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Main\FeatureControl
3. On the Edit menu, point to New, and then click Key.
4. Type FEATURE_IMAGING_MULTITHREAD_PROTECTION_WHEN_OPTIMIZED_KB942174, and then press ENTER.
5. Right-click FEATURE_IMAGING_MULTITHREAD_PROTECTION_WHEN_OPTIMIZED_KB942174, point to New, and then click DWORD Value.
6. Type iexplore.exe, and then press ENTER.
7. Right-click iexplore.exe, and then click Modify.
8. In the Value data box, type 1, and then click OK.
9. Exit Registry Editor.

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.

Windows Vista, x86-based versions

Windows Vista, x64-based versions

Hotfix information for Windows XP

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. 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

To install the hotfix, you must have Internet Explorer 7 and Windows XP Service Pack 2 installed.

Restart requirement

You have to restart your computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other previously released hotfixes.

Registry information

Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

To use this hotfix, follow these steps:

1. Click Start, type regedit in the Start Search box, and then press ENTER.
2. Locate the following registry subkey, and then click it:
   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Main\FeatureControl
3. On the Edit menu, point to New, and then click Key.
4. Type FEATURE_IMAGING_MULTITHREAD_PROTECTION_WHEN_OPTIMIZED_KB942174, and then press ENTER.
5. Right-click FEATURE_IMAGING_MULTITHREAD_PROTECTION_WHEN_OPTIMIZED_KB942174, point to New, and then click DWORD Value.
6. Type iexplore.exe, and then press ENTER.
7. Right-click iexplore.exe, and then click Modify.
8. In the Value data box, type 1, and then click OK.
9. Exit Registry Editor.

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.

Windows XP with SP2, x86-based versions

Hotfix information for Windows Server 2003

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. 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

To install the hotfix, you must have Internet Explorer 7 and Windows Server 2003 Service Pack 2 installed.

Restart requirement

You have to restart your computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other previously released hotfixes.

Registry information

Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

To use this hotfix, follow these steps:

1. Click Start, type regedit in the Start Search box, and then press ENTER.
2. Locate the following registry subkey, and then click it:
   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Main\FeatureControl
3. On the Edit menu, point to New, and then click Key.
4. Type FEATURE_IMAGING_MULTITHREAD_PROTECTION_WHEN_OPTIMIZED_KB942174, and then press ENTER.
5. Right-click FEATURE_IMAGING_MULTITHREAD_PROTECTION_WHEN_OPTIMIZED_KB942174, point to New, and then click DWORD Value.
6. Type iexplore.exe, and then press ENTER.
7. Right-click iexplore.exe, and then click Modify.
8. In the Value data box, type 1, and then click OK.
9. Exit Registry Editor.

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.

Windows Server 2003 with SP2, x86-based versions

Windows Server 2003 with SP2, x64-based versions

Windows Server 2003 with SP2, IA64-based versions

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. This problem was first corrected in Windows Vista Service Pack 1.

In Internet Explorer, two threads work with translucent layers. These threads are the UI thread and the image decoding thread.

The image decoding thread optimizes the image into a single-color PatBlt function. This thread determines the color by calling the SelectObject function on the HBITMAP object.

At the same time, the UI thread draws the image. Also, this thread determines the color by calling the SelectObject function on the HBITMAP object.

However, the HBITMAP object can only be selected in one device context (DC). Therefore, one of the two calls to the SelectObject function fails. If the decoding thread cannot call the SelectObject function, the solid color becomes incorrect. The solid color is used for the PatBlt function to perform future draw operations.

For more information about the Style property, visit the following Microsoft Web site:For information about the Filter property, visit the following Microsoft Web site: For more information about the SelectObject function, visit the following Microsoft Web site: For more information about the PatBlt function, visit the following Microsoft Web site: For more information, click the following article number to view the article in the Microsoft Knowledge Base: