32-bit browser applications may not work as expected in Internet Explorer 10

When you run Internet Explorer 10 in the desktop on a 64-bit version of Windows 8, add-ons that are written for the 32-bit browser (for example, Browser Helper Objects (BHOs), Toolbars, and ActiveX controls) do not work as expected.

This issue occurs when the following registry entry is set to 0:
HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main\TabProcGrowth
The Internet Explorer 10 Manager process is always a 64-bit process in 64-bit versions of Windows 8. This is an architecture change in Internet Explorer 10. By default, tab processes can be either 32-bit or 64-bit processes, except when the TabProcGrowth registry entry is set to 0. When this registry entry is set to 0, the tabs run in the same process as the manager process, which in this case is 64-bit. However, some browser add-ons do not have a 64-bit version. Therefore, they do not work as expected.
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows
To have us work around this issue for you, go to the "Fix it for me" section. If you prefer to work around this issue yourself, go to the "Let me fix it myself" section.

Fix it for me

To work around this issue, click the Fix it button or link. Then click Run in the File Download dialog box, and follow the steps in the Fix it wizard.

  • The Fix it solution will help you modify the value of TabProcGrowth registry entry to 'Medium'.
  • This wizard may be in English only. However, the automatic fix also works for other language versions of Windows.
  • If you are not on the computer that has the problem, save the Fix it solution to a flash drive or a CD and then run it on the computer that has the problem.
  • We would appreciate your feedback. To provide feedback or to report any issues with this solution, please leave a comment on the "Fix it for me" blog or send us an email message.

Let me fix it myself

To work around this issue, change the value of the TabProcGrowth registry entry to an integer number that is greater than 0. To do this, follow these steps:
  1. Swipe in from the right edge of the screen, and then tap Search. Or, if you are using a mouse, point to the lower-right corner of the screen, and then click Search.
  2. In the search box, type regedit.
  3. Tap or click the displayed Regedit icon. Locate and then select the following registry entry:
    HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main\TabProcGrowth
  4. Change the value of the registry entry.
Note If you do not want to change the registry setting, you may have to run add-ons that are written for 64-bit browsers. Contact the software vendor to check whether a 64-bit version of the add-on is available.
More information
For more information about the TabProcGrowth registry entry, go to the following Microsoft MSDN website:For more information about issues that may occur when you use a 64-bit version of Internet Explorer as the default version, go to the following Microsoft MSDN website:

Article ID: 2716529 - Last Review: 01/23/2013 09:47:00 - Revision: 2.0

Internet Explorer 10, Windows 8, Windows 8 Enterprise

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