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

Important

The Internet Explorer 11 desktop application will be retired and go out of support on June 15, 2022 (for a list of what's in scope, see the FAQ). The same IE11 apps and sites you use today can open in Microsoft Edge with Internet Explorer mode. Learn more here.

This article provides a workaround to solve the issue that some 32-bit browser applications not working as expected in Internet Explorer.

Original product version:   Internet Explorer 11, Internet Explorer 10, Windows 8, Windows 8 Enterprise
Original KB number:   2716529

Symptoms

When you run Internet Explorer 10 or Internet Explorer 11 in the desktop on a 64-bit version of Windows, 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

Cause

The Internet Explorer Manager process is always a 64-bit process in 64-bit versions of Windows 8 or later operating systems. 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.

Workaround

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, see How to back up and restore the registry in Windows.

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 select Search.

  2. In the search box, type regedit.

  3. Tap or select 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.